@article{ghorbani_li_qiu_marcus_scully_gharbi_luo_gupta_zeng_fraser_et al._2024, title={Current Progress in Aqueous Corrosion of Multi-Principal Element Alloys}, volume={6}, ISSN={["1543-1940"]}, DOI={10.1007/s11661-024-07473-x}, journal={METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE}, author={Ghorbani, M. and Li, Z. and Qiu, Y. and Marcus, P. and Scully, J. R. and Gharbi, O. and Luo, H. and Gupta, R. K. and Zeng, Z. R. and Fraser, H. L. and et al.}, year={2024}, month={Jun} }
 @article{witharamage_christudasjustus_walunj_borkar_gupta_2024, title={Effect of V Content on Corrosion Behavior of Al-V Alloys Produced by Mechanical Alloying and Subsequent Spark Plasma Sintering}, volume={171}, ISSN={["1945-7111"]}, url={https://doi.org/10.1149/1945-7111/ad2d1b}, DOI={10.1149/1945-7111/ad2d1b}, abstractNote={Al-V alloys produced via high-energy ball milling have been reported to show simultaneous improvement of corrosion resistance and mechanical properties compared to traditional Al alloys. In these alloys, V content plays a crucial role in increasing or decreasing the corrosion resistance. Therefore, the effect of V and microstructure on corrosion of high-energy ball milled and subsequently spark plasma sintered Al-xV alloys (x = 2, 5, 10 at%) has been studied. Cyclic potentiodynamic polarization tests and electrochemical impedance spectroscopic analysis revealed the increment of V content up to 5 at% enhanced the corrosion resistance of the alloy. However, highly heterogeneous microstructure in Al-10 at%V resulted in significant localized corrosion over the immersion time. The electrochemical impedance spectroscopy studies over 14 days of immersion revealed underlying corrosion mechanisms.}, number={3}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Witharamage, Chathuranga Sandamal and Christudasjustus, J. and Walunj, G. and Borkar, T. and Gupta, R. K.}, year={2024}, month={Mar} }
 @article{digole_desai_christopher_bohara_witharamage_kothapalli_gupta_borkar_2024, title={Improved Tribological Performance of Nitride-Reinforced Biocompatible Titanium-Niobium-Zirconium-Tantalum (TNZT) Alloys for Advanced Orthopedic Applications}, volume={14}, ISSN={["2075-4701"]}, url={https://doi.org/10.3390/met14010122}, DOI={10.3390/met14010122}, abstractNote={β-titanium (β-Ti) alloys are used in various biomedical applications, especially for orthopedic implants, due to their superior biocompatibility, excellent corrosion resistance, and enhanced mechanical properties. However, the inferior tribological properties of β-Ti alloys lead to fretting wear and a strong tendency to seize, which is a major concern in orthopedic applications involving continuous friction. This work aims to address this issue by incorporating biocompatible nitrides in Ti-Nb-Zr-Ta (TNZT) β-Ti alloys. TNZT composites comprising 2 wt.% of biocompatible nitrides (TiN, NbN, ZrN, and TaN) were prepared using high-energy ball milling followed by spark plasma sintering. All the nitrides improved the hardness and wear resistance of TNZT alloys and showed excellent biocompatibility. TNZT-2 wt.% TiN showed the average highest hardness of 311.8 HV and the lowest coefficient of friction of 0.659, suggesting the highest efficiency of TiN in improving the tribological performance of TNZT alloys. The underlying mechanisms behind the superior performance of nitride-reinforced TNZT composites are discussed in detail. The effect of TiN concentration was also studied by preparing TNZT composites with 5 and 10 wt.% TiN, which showcased a higher hardness of 388.5 HV and 444.3 HV, respectively. This work will aid in producing superior β-Ti alloys for advanced orthopedic applications.}, number={1}, journal={METALS}, author={Digole, Satyavan and Desai, Jay and Christopher, Calvin and Bohara, Smriti and Witharamage, Chathuranga Sandamal and Kothapalli, Chandra and Gupta, Rajeev Kumar and Borkar, Tushar}, year={2024}, month={Jan} }
 @article{vukkum_sanborn_shepherd_saptarshi_basu_horn_gupta_2024, title={Influence of Spatter on Porosity, Microstructure, and Corrosion of Additively Manufactured Stainless Steel Printed Using Different Island Size}, volume={14}, ISSN={["2073-4352"]}, url={https://doi.org/10.3390/cryst14040328}, DOI={10.3390/cryst14040328}, abstractNote={Specimens of 316 L stainless steel were printed using laser powder bed fusion (LPBF), a popular metal additive manufacturing (AM) technique, with varying island sizes. Not many researchers have considered the impact of spatter while optimizing LPBF printing parameters. In this research, the influence of spatter was considered while also investigating the effect of varied island size on the microstructure, surface roughness, microhardness, and corrosion resistance of LPBF-316 L. No correlation was observed between surface roughness or microhardness and minor variations in island size. However, a correlation was drawn between varied island sizes and porosity in LPBF-316 L. The specimens associated with larger island sizes showed significantly enhanced corrosion resistance due to fewer manufacturing defects and reduced porosity, attributed to the minimal influence of the spatter. Based on analysis, the LPBF parameters were revised, which lead to superior corrosion resistance of LPBF-316 L, attributed to high density and reduced porosity.}, number={4}, journal={CRYSTALS}, author={Vukkum, Venkata Bhuvaneswari and Sanborn, Taylor and Shepherd, John and Saptarshi, Sourabh and Basu, Rakesh and Horn, Timothy and Gupta, Rajeev Kumar}, year={2024}, month={Apr} }
 @article{vukkum_ansell_nieto_gupta_2024, title={Intergranular Corrosion of CNT-Reinforced and Laser Powder Bed Fusion-Printed 316L Stainless Steel}, volume={76}, ISSN={["1543-1851"]}, DOI={10.1007/s11837-023-06165-y}, number={1}, journal={JOM}, author={Vukkum, Venkata Bhuvaneswari and Ansell, Troy Y. and Nieto, Andy and Gupta, Rajeev Kumar}, year={2024}, month={Jan}, pages={232–237} }
 @article{digole_karki_mugale_choudhari_gupta_borkar_2024, title={Spark Plasma Sintering of Pure Titanium: Microstructure and Mechanical Characteristics}, url={https://doi.org/10.3390/ma17143469}, DOI={10.3390/ma17143469}, abstractNote={The versatility of titanium (Ti) allows it to be employed in various industries, from aerospace engineering to medical technology, highlighting its significance in modern manufacturing and engineering processes. Spark plasma sintering (SPS) is currently being explored to enhance its properties further and broaden its application range. The current study focuses on exploring and optimizing the effect of SPS temperature (800, 900, 1000, 1100, 1200, and 1400 °C) on pure Ti sintered at 60 MPa in a controlled argon environment with a dwell time of 5 min. All the prepared samples were highly dense with a relative density above 99%, but exhibited significant variations in grain size (10 to 57 µm), tensile yield strength (488 to 700 MPa), ultimate tensile strength (597 to 792 MPa), and ductility (4 to 7%). A microstructural investigation was performed using XRD, SEM, and EDS to predict the influence of sintering temperature on the formation of different phases. The XRD patterns of all sintered samples showed the presence of single-phase α-Ti with hexagonally close-packed Ti. This work is a step forward in optimizing SPS-processed Ti’s physical and mechanical properties for enhanced structural and biomedical applications.}, journal={Materials}, author={Digole, Satyavan and Karki, Sanoj and Mugale, Manoj and Choudhari, Amit and Gupta, Rajeev Kumar and Borkar, Tushar}, year={2024}, month={Jul} }
 @article{gupta_vukkum_darwish_2023, title={(Corrosion Division Rusty Award for Mid-Career Excellence) Enhancing the Corrosion Resistance of Additively Manufactured Metallic Materials: The Role of Feedstock Modification}, url={https://doi.org/10.1149/MA2023-02111083mtgabs}, DOI={10.1149/MA2023-02111083mtgabs}, abstractNote={  	The properties of metallic materials produced through additive manufacturing (AM), including their corrosion behavior, depend on various parameters such as the type of AM technique, processing parameters, built environment, and the feedstock used [1]. These factors collectively influence the occurrence of processing defects and the microstructure of the alloy, which can be controlled through feedstock modifications. To illustrate the impact of feedstock modification on both microstructure and corrosion, two examples will be presented. These examples will compare the corrosion behavior of additively manufactured 316L stainless steel (SS) produced using three different types of feedstocks: the as-received feedstock, feedstock modified with CrN, and feedstock modified with carbon nanotubes. The feedstock modification was carried out by ball milling of commercial 316L SS powder with the selected additive [2-4]. Test coupons were produced by laser powder bed fusion of the commercial feedstock and modified feedstock. Corrosion resistance was evaluated using cyclic potentiodynamic polarization tests in NaCl solution. The pitting and repassivation potentials of the 316L SS produced by modified feedstock were significantly higher compared to those of 316L SS produced using as-received feedstock [2-4]. The mechanistic aspects of the feedstock modifications and their influence on corrosion behavior will be discussed in detail.}, journal={ECS Meeting Abstracts}, author={Gupta, Rajeev Kumar and Vukkum, Bhuvana and Darwish, Ahmed A}, year={2023}, month={Dec} }
 @article{christudasjustus_felde_witharamage_esquivel_darwish_winkler_gupta_2023, title={Age-hardening behavior, corrosion mechanisms, and passive film structure of nanocrystalline Al-V supersaturated solid solution}, volume={135}, ISSN={["1941-1162"]}, url={https://doi.org/10.1016/j.jmst.2022.06.044}, DOI={10.1016/j.jmst.2022.06.044}, abstractNote={The effect of age-hardening on microstructure, hardness, and corrosion of an Al-5at.%V alloy, produced using high-energy ball milling and subsequent cold compaction, has been investigated. The alloy exhibited a grain size below 100 nm and extremely high solid solubility of V in Al (3.1 at.%). The age-hardening was carried out at 150, 200, and 250 °C. The peak-aged condition of 150 °C demonstrated the highest hardness—transpired from grain refinement, precipitation, and solid solution hardening. The corrosion resistance of the Al-5at.%V alloy was studied as a function of aging conditions. The peak-aged condition retained the corrosion resistance while it deteriorated in the over-aged condition. Nonetheless, the corrosion resistance of the ball-milled Al alloys in all the aging conditions was superior to that of pure Al. The passive film structure and origin of corrosion were studied using scanning/transmission electron microscopy (S/TEM). The high corrosion resistance of the alloy was attributed to the V enrichment at the film/metal interface and deposition of V on the cathodic phases, which suppresses the dissolution of Al within the pit and therefore promotes repassivation in the early stages of corrosion.}, journal={JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY}, author={Christudasjustus, J. and Felde, M. R. and Witharamage, C. S. and Esquivel, J. and Darwish, A. . A. . and Winkler, C. and Gupta, R. K.}, year={2023}, month={Feb}, pages={1–12} }
 @article{daroonparvar_helmer_ralls_khan_kasar_menezes_misra_gupta_2023, title={Enhanced wear and corrosion resistances of Al coated Mg alloy using high pressure cold sprayed commercially pure-zirconium coating}, volume={346}, ISSN={["1873-4979"]}, DOI={10.1016/j.matlet.2023.134473}, abstractNote={Commercially pure (CP) Zr coating with high microhardness (387 ± 26 HV0.025) was produced on CP-Al coated Mg alloy by a high pressure cold spray (HPCS) system. Substantial densification of Al layers, beneath deposited Zr coating, was observed because of shot-peening influence by Zr particles. The electrochemical impedance spectroscopy after 24 h of immersion in 3.5 wt% NaCl electrolyte revealed highest charge transfer resistance (Rct), polarization resistance (Rpol), and corrosion resistance (|Z|f=0.01Hz) for the Zr/Al coated Mg alloy. Also, wear rate for the Zr/Al coating was lowest which could be attributed to its higher hardness caused by smaller crystallite size and higher dislocation density.}, journal={MATERIALS LETTERS}, author={Daroonparvar, M. and Helmer, A. and Ralls, A. M. and Khan, M. U. Farooq and Kasar, A. K. and Menezes, P. L. and Misra, M. and Gupta, R. K.}, year={2023}, month={Sep} }
 @article{christudasjustus_vukkum_gupta_2023, title={Evolution of surface film in AA2024-T3 after a long-term immersion in NaCl solution}, volume={215}, ISSN={["1879-0496"]}, url={http://dx.doi.org/10.1016/j.corsci.2023.111056}, DOI={10.1016/j.corsci.2023.111056}, abstractNote={Surface films of AA2024-T3 after immersion in 0.1 M NaCl for 14 days, 6 months, and 1 year have been investigated using scanning electron microscopy. The corrosion product generated on the surface over the immersion period was comprised of porous outer and compact inner layers. The Cu enrichment at the corrosion product/metal interface and Cu clusters within the surface films have been observed. Exfoliation corrosion was observed, which allows the electrolyte to migrate through exfoliated path and cause rapid corrosion at sub-surface level. Mechanistic aspects of surface film, Cu cluster formation, and corrosion under the surface film have been discussed.}, journal={CORROSION SCIENCE}, publisher={Elsevier BV}, author={Christudasjustus, J. and Vukkum, V. B. and Gupta, R. K.}, year={2023}, month={May} }
 @article{vukkum_ansell_nieto_gupta_2023, title={Intergranular Corrosion of CNT-Reinforced and Laser Powder Bed Fusion-Printed 316L Stainless Steel}, volume={10}, ISSN={["1543-1851"]}, DOI={10.1007/s11837-023-06165}, journal={JOM}, author={Vukkum, Venkata Bhuvaneswari and Ansell, Troy Y. and Nieto, Andy and Gupta, Rajeev Kumar}, year={2023}, month={Oct} }
 @article{vukkum_delvecchio_christudasjustus_storck_gupta_2023, title={Intergranular Corrosion of Feedstock Modified-Additively Manufactured Stainless Steel After Sensitization}, volume={79}, ISSN={["1938-159X"]}, url={https://doi.org/10.5006/4245}, DOI={10.5006/4245}, abstractNote={Laser powder bed fusion (LPBF), a metal additive manufacturing technique, was conducted on feedstock-modified 316L stainless steel (316L) powder produced by ball-milling of commercial 316L and 1 wt% additive (cerium oxide—CeO2, lanthanum (III) nitrate hexahydrate—La(NO3)3·6H2O, and chromium nitride—CrN). The feedstock-modified LPBF-316L specimens were sensitized at 675°C for 24 h, and the influence of additives on intergranular corrosion (IGC) was investigated following ASTM G108-94 and A262-14 standards. The LPBF-316L with La(NO3)3·6H2O showed higher IGC resistance. The microstructure of the LPBF specimen was investigated and correlated to understand the improved IGC resistance of LPBF-316L with La(NO3)3·6H2O additive.}, number={6}, journal={CORROSION}, author={Vukkum, Venkata Bhuvaneswari and Delvecchio, Evan and Christudasjustus, Jijo and Storck, Steven and Gupta, Rajeev Kumar}, year={2023}, month={Jun}, pages={624–636} }
 @article{o'brien_christudasjustus_delvecchio_birbilis_gupta_2023, title={Microstructure and corrosion of CrFeMnV multi-principal element alloy}, volume={222}, ISSN={["1879-0496"]}, DOI={10.1016/j.corsci.2023.111403}, abstractNote={A multi-principal element alloy consisting of equiatomic concentrations of Cr, Fe, Mn, and V was produced by arc melting. The combination of X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy indicated that the CrFeMnV MPEA was comprised of a BCC matrix with a dispersion of a secondary phase. Cyclic potentiodynamic polarization tests in 0.6 M NaCl revealed high corrosion resistance – superior to that of stainless steel 304L, as evident from high breakdown and repassivation potentials. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry provided insight into the formed multi-layer surface film after constant immersion and potentiostatic conditioning.}, journal={CORROSION SCIENCE}, author={O'Brien, S. P. and Christudasjustus, J. and Delvecchio, E. and Birbilis, N. and Gupta, R. K.}, year={2023}, month={Sep} }
 @article{daroonparvar_helmer_ralls_khan_kasar_gupta_misra_shao_menezes_shamsaei_2023, title={Pitting corrosion behavior and corrosion protection performance of cold sprayed double layered noble barrier coating on magnesium-based alloy in chloride containing solutions}, volume={11}, ISSN={["2213-9567"]}, DOI={10.1016/j.jma.2023.09.008}, abstractNote={Nitrogen processed, cold sprayed commercially pure (CP)-Al coatings on Mg-based alloys mostly lack acceptable hardness, wear resistance and most importantly are highly susceptible to localized corrosion in chloride containing solutions. In this research, commercially pure α-Ti top coating having good pitting potential (∼ 1293 mVSCE), high microhardness (HV0.025: 263.03) and low wear rate was applied on a CP-Al coated Mg-based alloy using high pressure cold spray technology. Potentiodynamic polarization (PDP) curves indicated that the probability of transition from metastable pits to the stable pits for cold spayed (CS) Al coating is considerably higher compared to that with the CS Ti top coating (for Ti/Al/Mg system). In addition, CS Ti top coating was in the passivation region in most pH ranges even after 48 h immersion in 3.5 wt% NaCl solution. The stored energy in the CS Ti top coating (as a passive metal) was presumed to be responsible for the easy passivation. Immersion tests indicated no obvious pits formation on the intact CS Ti top coating surface and revealed effective corrosion protection performance of the CS double layered noble barrier coatings on Mg alloys in 3.5 wt% NaCl solution even after 264 h.}, number={9}, journal={JOURNAL OF MAGNESIUM AND ALLOYS}, author={Daroonparvar, M. and Helmer, A. and Ralls, A. M. and Khan, M. U. Farooq and Kasar, A. K. and Gupta, R. K. and Misra, M. and Shao, S. and Menezes, P. L. and Shamsaei, N.}, year={2023}, month={Sep}, pages={3099–3119} }
 @book{gupta_shrivastava_deshmukh_patil_giri_chadge_2023, title={Recent Advances in Material, Manufacturing, and Machine Learning}, url={https://doi.org/10.1201/9781003358596}, DOI={10.1201/9781003358596}, author={Gupta, Rajiv and Shrivastava, Naveen Kumar and Deshmukh, Devendra and Patil, Awanikumar P. and Giri, Jayant and Chadge, R.B.}, year={2023}, month={Apr} }
 @book{gupta_shrivastava_deshmukh_patil_giri_chadge_2023, title={Recent Advances in Material, Manufacturing, and Machine Learning}, url={https://doi.org/10.1201/9781003370628}, DOI={10.1201/9781003370628}, author={Gupta, Rajiv and Shrivastava, Naveen Kumar and Deshmukh, Devendra and Patil, Awanikumar P. and Giri, Jayant and Chadge, R.B.}, year={2023}, month={Apr} }
 @article{daroonparvar_helmer_ralls_kasar_khan_menezes_misra_shao_gupta_2023, title={Study on the corrosion behavior of cold sprayed aluminum-based coatings on Mg-based alloy in chloride containing solution: Effect of N-2 processing gas temperature}, volume={223}, ISSN={["1879-0496"]}, DOI={10.1016/j.corsci.2023.111454}, abstractNote={Cold sprayed (CS) commercially pure Al-based coatings (processed at various propellent N2 gas temperatures) were applied on Mg-based alloys. The porosity percentage of the CS coatings decreased, and the flattening ratio increased as the N2 processing gas temperature reduced due to the effect of the in-situ tamping densification. This also led to the obvious reduction of wear rate of the CS Al-based coatings. In the present research, among the Al coated Mg alloys having higher general corrosion resistance (i.e., higher |Z|f=0.01 Hz and polarization resistance at the corrosion potential (Rpol)), a decrease in dislocation density and microstrain was postulated to lead to the improvement of overall pitting behavior of the CS Al-based coating (processed at the lowest N2 propellent gas temperature) after 12 days immersion in 3.5 wt% NaCl solution.}, journal={CORROSION SCIENCE}, author={Daroonparvar, M. and Helmer, A. and Ralls, A. M. and Kasar, A. K. and Khan, M. U. Farooq and Menezes, P. L. and Misra, M. and Shao, S. and Gupta, R. K.}, year={2023}, month={Oct} }
 @article{christudasjustus_witharamage_vukkum_walunj_borkar_gupta_2023, title={Surface Film Formation on Al-V Alloys with Far-From-Equilibrium Microstructure}, volume={170}, ISSN={["1945-7111"]}, url={https://doi.org/10.1149/1945-7111/acc7ce}, DOI={10.1149/1945-7111/acc7ce}, abstractNote={Nanocrystalline supersaturated Al-V alloys produced by high-energy ball milling have been reported to exhibit enhanced corrosion resistance and mechanical properties compared to commercial Al alloys. Corrosion of passive alloys such as Al-V alloy relies on the characteristics of the surface film, which is studied using scanning/transmission electron microscopy and time-of-flight secondary ion mass spectrometry. The effect of microstructure and composition on the surface film has been investigated after different immersion periods (30 min, 2 h, and 1 day) in 0.1 M NaCl. The surface film was complex and composed of oxidized Al and V. The heterogeneous surface film was observed due to the presence of secondary phases and initiation of localized corrosion. The void formation was observed beneath the surface film that would potentially cause pitting corrosion. The generation of nano-sized voids was dependent on grain orientation. Compared to pure Al, the chloride penetration is suppressed in Al-V alloys. The effect of composition and microstructure on surface film formation and attendant corrosion behavior is discussed herein.}, number={3}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Christudasjustus, J. and Witharamage, C. S. and Vukkum, V. B. and Walunj, G. and Borkar, T. and Gupta, R. K.}, year={2023}, month={Mar} }
 @article{witharamage_darwish_christudasjustus_soltis_gupta_2023, title={Time-Dependent Corrosion Behavior of Aluminum Using Advanced Electrochemical and Characterization Techniques}, volume={170}, ISSN={["1945-7111"]}, url={https://doi.org/10.1149/1945-7111/acfb40}, DOI={10.1149/1945-7111/acfb40}, abstractNote={The time-dependent corrosion behavior of pure aluminum (Al) in a chloride-containing environment was investigated using various electrochemical and characterization techniques for up to 336 h. Transmission electron microscopic and secondary ion mass spectroscopic analysis revealed the continuous dissolution of the surface film over the immersion time. In the meantime, the increasing passive oxide thickness resulted in the surface film resistance enhancement over the immersion time, as indicated by the electrochemical impedance spectroscopic analysis. The electrochemical noise measurements showed an increase in the corrosion kinetics with immersion time until 60 h because of the accelerated localized corrosion in the early stage of immersion. However, an inhibition in corrosion kinetics occurred after longer immersion times due to corrosion product deposition inside the pit.}, number={9}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Witharamage, C. S. and Darwish, A. A. and Christudasjustus, J. and Soltis, J. and Gupta, R. K.}, year={2023}, month={Sep} }
 @article{nieto_vukkum_jalagam_nema_budan_gupta_ansell_2022, title={3D printed carbon nanotube reinforced stainless steel via selective lase melting}, volume={8}, ISSN={["2159-6867"]}, DOI={10.1557/s43579-022-00200-w}, abstractNote={Carbon nanotubes (CNT) are integrated into 316L stainless steel (SS) powder feedstocks and 3D-printed using selective laser melting (SLM). Ball milling is used to disperse CNT clusters homogeneously onto the surface of 316L SS powders with minimal damage to the CNTs. Hardness increased by 35% and wear was reduced by 70% with the addition of 2 vol% CNT, relative to SLM 316L SS. The addition of CNTs increased the water contact angle and retained the desirable corrosion resistance of SLM 316L SS, demonstrating the potential of 3D-printed SS-CNT composites for use in structural marine applications. Graphical abstract}, journal={MRS COMMUNICATIONS}, author={Nieto, Andy and Vukkum, Venkata Bhuvaneswari and Jalagam, Prajna and Nema, Kanishq and Budan, Justin and Gupta, Rajeev Kumar and Ansell, Troy Y.}, year={2022}, month={Aug} }
 @article{christudasjustus_larimian_esquivel_gupta_darwish_borkar_gupta_2022, title={Aluminum alloys with high elastic modulus}, volume={320}, ISSN={["1873-4979"]}, DOI={10.1016/j.matlet.2022.132292}, abstractNote={Binary Al-5M alloys, containing 5 at.% alloying element (M: Cr, Si, Nb, Mo, and V), have been produced by high-energy ball milling and subsequent spark plasma sintering. X-ray diffraction analysis indicated the solid solubility of the alloying elements to be several orders of magnitude higher than that predicted by the phase diagram. The elastic modulus and hardness of Al-5M alloys, analyzed using nanoindentation, were significantly higher than the commercial Al alloys. High elastic modulus was attributed to the decrease in lattice parameters as a result of the extended solid solubility of the alloying elements.}, journal={MATERIALS LETTERS}, author={Christudasjustus, J. and Larimian, T. and Esquivel, J. and Gupta, S. and Darwish, A. A. and Borkar, T. and Gupta, R. K.}, year={2022}, month={Aug} }
 @inbook{soltis_gupta_2022, title={Corrosion Management: Current Status and its Relevance for Assets Operating in a Circular Economy, Corrosion Management for a Sustainable Future}, ISBN={9781575903880}, booktitle={Corrosion Management for a Sustainable Future}, publisher={NACE Publications}, author={Soltis, J. and Gupta, R.K.}, editor={Taylor, C. and Sanchez, A.N.Editors}, year={2022} }
 @article{vukkum_darwish_christudasjustus_storck_gupta_2022, title={Corrosion Performance of Additively Manufactured 316L Stainless Steel Produced By Feedstock Modification}, url={https://doi.org/10.1149/MA2022-01161013mtgabs}, DOI={10.1149/MA2022-01161013mtgabs}, abstractNote={  	Additive manufacturing (AM) is an emerging technology that can build 3d-component in a single step via the layer-by-layer process. Selective laser melting (SLM) is a popular powder bed fusion (PBF) – AM technique that involves rapid heating and cooling cycles with broad temperature gradients and complex thermal history. Moreover, the SLM components are often reported to have lower build densification due to stochastic porosity. The complex thermal cycles and stochastic porosity can negatively influence the corrosion performance of SLM printed 316L Stainless steel (SLM-316L) alloys. The corrosion performance of SLM-316L can be improved by optimizing the SLM processing parameters to improve the density and/or performing post-processing. However, post-processing increases the cost and time to deliver the components and is desired to avoid. Therefore, modifying the feedstock to increase corrosion resistance and therefore tolerance of the pores would help streamline the workflow and eliminate expensive post-manufacturing steps. In this research, the feedstock modification was conducted using ball milling of various additives and 316L powder. Corrosion performance of the SLM specimen was dependent on the additive used to modify the feedstock. Some of the additives imparted significantly improved corrosion performance, as evident from the high pitting and repassivation potentials and absence of metastable pitting. Observed corrosion performance was correlated with the microstructure which was studied using scanning and transmission electron microscopes. X-ray photoelectron spectroscopy and time of flight secondary ion mass spectrometry was used to study the surface film. Role of additives on microstructure and corrosion performance will be discussed.    }, journal={ECS Meeting Abstracts}, author={Vukkum, Venkata Bhuvaneswari and Darwish, Ahmed A and Christudasjustus, Jijo and Storck, Steven and Gupta, Rajeev Kumar}, year={2022}, month={Jul} }
 @article{ozdemir_witharamage_christudasjustus_darwish_okuyucu_gupta_2022, title={Corrosion behavior of a bulk nanocrystalline Al-Fe alloy}, volume={209}, ISSN={["1879-0496"]}, DOI={10.1016/j.corsci.2022.110727}, abstractNote={Nanocrystalline Al-Fe alloy, with uniform microstructure and high solid solubility of Fe, has been produced by high-energy ball milling. Cyclic potentiodynamic polarization tests revealed high pitting potential. Hardness and corrosion resistance of the Al-Fe alloy were higher than any commercial Al alloy. High hardness and corrosion resistance were attributed to the nanocrystalline structure and formation of solid solution. X-ray photoelectron spectroscopy, secondary ion mass spectrometry, and scanning transmission electron microscopy indicated the incorporation of Fe to the surface film and Fe enrichment at the alloy/surface film interface, which were attributed to the enhanced corrosion performance.}, journal={CORROSION SCIENCE}, author={Ozdemir, F. and Witharamage, C. S. and Christudasjustus, J. and Darwish, A. A. and Okuyucu, H. and Gupta, R. K.}, year={2022}, month={Dec} }
 @article{ozdemir_witharamage_darwish_okuyucu_gupta_2022, title={Corrosion behavior of age hardening aluminum alloys produced by high-energy ball milling}, volume={900}, ISSN={["1873-4669"]}, url={http://dx.doi.org/10.1016/j.jallcom.2021.163488}, DOI={10.1016/j.jallcom.2021.163488}, abstractNote={The influence of high energy-ball milling (HEBM) on corrosion and hardness of age hardening aluminum alloys was investigated. Nanocrystalline age hardening (AA2024, AA6061 and AA7075) alloys were produced by HEBM of pre-alloyed powder and subsequent cold compaction under uniaxial pressure of 3 GPa. Cyclic potentiodynamic polarization and immersion tests were conducted in 0.6 M NaCl solution which revealed significantly increased pitting and protection potentials in the HEBM alloys compared to wrought alloys of same composition. X-ray diffraction analysis and transmission electron microscopy indicated grain refinement below 100 nm in the ball milled alloys which was the major strengthening mechanism in the age hardening HEBM alloys. The superior corrosion resistance and hardness of the age hardening ball milled alloys were attributed to nanocrystalline structure, extended solid solubility and homogenous microstructure- free from coarse intermetallic phases.}, journal={JOURNAL OF ALLOYS AND COMPOUNDS}, publisher={Elsevier BV}, author={Ozdemir, Furkan and Witharamage, Chathuranga Sandamal and Darwish, Ahmed Abdelazim and Okuyucu, Hasan and Gupta, Rajeev Kumar}, year={2022}, month={Apr} }
 @article{witharamage_christudasjustus_smith_gao_gupta_2022, title={Corrosion behavior of an in situ consolidated nanocrystalline Al-V alloy}, volume={6}, ISSN={["2397-2106"]}, url={https://doi.org/10.1038/s41529-022-00225-5}, DOI={10.1038/s41529-022-00225-5}, abstractNote={Abstract}, number={1}, journal={NPJ MATERIALS DEGRADATION}, author={Witharamage, C. S. and Christudasjustus, J. and Smith, J. and Gao, W. and Gupta, R. K.}, year={2022}, month={Feb} }
 @article{vukkum_ozdemir_storck_gupta_2022, title={Corrosion performance of feedstock modified - Additively manufactured stainless steel}, volume={209}, ISSN={["1879-0496"]}, DOI={10.1016/j.corsci.2022.110724}, abstractNote={Feedstock modified powders were produced by ball-milling commercial 316 L stainless steel powder and 1 wt% additive (Cerium oxide–CeO2, lanthanum (III) nitrate hexahydrate–La(NO3)30.6 H2O and chromium nitride–CrN). Laser-powder bed fusion (L-PBF) was performed on modified feedstock using 180, 200, and 220 W laser power. The influence of additives on microstructure and corrosion performance was investigated on the as-printed and ground/polished conditions of L-PBF-316 L-additive. The corrosion performance was dependent on the type of the additives. The microstructure of the alloys was correlated with the observed corrosion behavior.}, journal={CORROSION SCIENCE}, author={Vukkum, V. B. and Ozdemir, Furkan and Storck, Steven and Gupta, R. K.}, year={2022}, month={Dec} }
 @article{witharamage_alrizqi_darwish_nieto_gupta_2022, title={Corrosion-Resistant Sacrificial Metallic Coatings Produced By Cold-Spray for Al Alloys}, url={https://doi.org/10.1149/MA2022-01161017mtgabs}, DOI={10.1149/MA2022-01161017mtgabs}, abstractNote={  	Corrosion is a massive disaster in many sectors that caused the loss of billions of dollars. For example, it was reported that the total direct estimated cost of corrosion was about $ 276 billion in 1998 in the US, which is 3.1% of the nation’s GDP. Therefore, a necessity to develop methods to overcome this challenge arose in the last few decades. Thus, the development of corrosion resistive coatings is significantly attracted researchers' attention. In combination with the corrosion inhibitors, organic and conversion coatings are used to improve the corrosion resistance of high-strength Al alloys. However, many corrosion inhibitors are carcinogenic: Chromate conversion coating performed very well, but alternative options need to be explored due to restrictions on its applications due to the health and environmental regulations. Moreover, organic coatings provide good corrosion resistance, but poor wear resistance and mechanical damage lead to corrosion issues. Metallic coatings are an alternative, and galvanized steel is one of the prominent examples. However, metallic coatings produced by elements such as Cr, Ni, Ti, or Ta are noble for Al or Mg-based alloys. Therefore, in any event of coating breakdown, the substrate would be more active and act as an anode and, corrode rapidly by galvanic interaction. Thus, such metallic coatings produced by the above-mentioned corrosion resistance elements are not very attractive for Al alloys.}, journal={ECS Meeting Abstracts}, author={Witharamage, Chathuranga S and Alrizqi, Mohammed A and Darwish, Ahmed A and Nieto, Andy and Gupta, Rajeev Kumar}, year={2022}, month={Jul} }
 @article{witharamage_alrizqi_chirstudasjustus_darwish_ansell_nieto_gupta_2022, title={Corrosion-resistant metallic coatings for aluminum alloys by cold spray}, volume={209}, ISSN={0010-938X}, url={http://dx.doi.org/10.1016/j.corsci.2022.110720}, DOI={10.1016/j.corsci.2022.110720}, abstractNote={An Al-V alloy powder produced by high-energy ball milling has been cold sprayed on an AA2024-T3 substrate. The corrosion resistance of cold sprayed alloy, represented by the corrosion current density and pitting potential, was significantly higher than the substrate. Furthermore, a zero-resistance ammeter test revealed that the coating was anodic to the substrate, which would provide cathodic protection in any event of coating breakdown. The wear resistance of the coating was almost four times higher than that of the substrate.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Witharamage, Chathuranga S. and Alrizqi, Mohammed A. and Chirstudasjustus, Jijo and Darwish, Ahmed A. and Ansell, Troy and Nieto, Andy and Gupta, Rajeev K.}, year={2022}, month={Dec}, pages={110720} }
 @article{patil_nartu_ozdemir_banerjee_gupta_borkar_2022, title={Effect of Graphene Morphology on the Microstructure, Mechanical and Tribological Behavior of Nickel Matrix Composites}, volume={10}, ISSN={["1543-1851"]}, DOI={10.1007/s11837-022-05532-5}, journal={JOM}, author={Patil, Amit and Nartu, Mohan Sai Kiran Kumar Yadav and Ozdemir, Furkan and Banerjee, Raj and Gupta, Rajeev Kumar and Borkar, Tushar}, year={2022}, month={Oct} }
 @article{vukkum_christudasjustus_darwish_storck_gupta_2022, title={Enhanced corrosion resistance of additively manufactured stainless steel by modification of feedstock}, volume={6}, ISSN={["2397-2106"]}, url={https://doi.org/10.1038/s41529-021-00215-z}, DOI={10.1038/s41529-021-00215-z}, abstractNote={Abstract}, number={1}, journal={NPJ MATERIALS DEGRADATION}, publisher={Springer Science and Business Media LLC}, author={Vukkum, V. B. and Christudasjustus, J. and Darwish, A. A. and Storck, S. M. and Gupta, R. K.}, year={2022}, month={Jan} }
 @article{ozdemir_gupta_2022, title={Influence of vanadium addition on corrosion behavior of high-energy ball milled aluminum alloy 2024}, volume={9}, ISSN={["1521-4176"]}, url={https://doi.org/10.1002/maco.202213478}, DOI={10.1002/maco.202213478}, abstractNote={Abstract}, journal={MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION}, author={Ozdemir, Furkan and Gupta, Rajeev K.}, year={2022}, month={Sep} }
 @article{ozdemir_christudasjustus_vukkum_okuyucu_gupta_2022, title={Need of an Inert Atmosphere for High-Energy Ball Milling of Al Alloys}, volume={9}, ISSN={["1544-1024"]}, url={https://doi.org/10.1007/s11665-022-07309-y}, DOI={10.1007/s11665-022-07309-y}, journal={JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE}, author={Ozdemir, F. and Christudasjustus, J. and Vukkum, V. B. and Okuyucu, H. and Gupta, R. K.}, year={2022}, month={Sep} }
 @article{christudasjustus_darwish_witharamage_gupta_terryn_2022, title={Passive Film Structure and Corrosion Initiation in Al Alloys with Far-from-Equilibrium Compositions and Microstructures}, url={https://doi.org/10.1149/MA2022-0211724mtgabs}, DOI={10.1149/MA2022-0211724mtgabs}, abstractNote={  	Al alloys with far-from-equilibrium compositions and microstructures are reported to possess high corrosion resistance and strength. These alloys produced are by non-equilibrium processing techniques such as high-energy ball milling, sputtering, and ion implantation. Depending on the processing techniques and conditions, the microstructure of the alloys could be heterogeneous. For example, alloys produced by high-energy ball milling and subsequent consolidation comprise a matrix with high solid solubility of the solute and uniformly distributed secondary phases. Such a heterogeneous microstructure is expected to influence the passive film composition and localized corrosion mechanisms. In the present study, passive film composition on the ball-milled alloys was studied using a combination of scanning transmission electron microscope, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry (SIMS). Additionally, pits and regions near pits were investigated which helped in understanding factors causing pit initiation and repassivation.    }, journal={ECS Meeting Abstracts}, author={Christudasjustus, Jijo and Darwish, Ahmed A and Witharamage, Chathuranga S and Gupta, Rajeev Kumar and Terryn, Herman Albert}, year={2022}, month={Oct} }
 @misc{vukkum_gupta_2022, title={Review on corrosion performance of laser powder-bed fusion printed 316L stainless steel: Effect of processing parameters, manufacturing defects, post-processing, feedstock, and microstructure}, volume={221}, ISSN={["1873-4197"]}, DOI={10.1016/j.matdes.2022.110874}, abstractNote={The applications of laser-powder bed fusion (LPBF), an emerging additive manufacturing (AM) technique, are rapidly growing in various industries. The superior and consistent mechanical and corrosion properties of LPBF-printed components are essential for engineering applications. The 316L stainless steel (SS) is an essential alloy with widespread applications from household items to nuclear and aerospace industries. Extensive research is conducted to understand and improve the mechanical properties of LPBF printed 316L SS. Studying the corrosion behavior of LPBF printed 316L has attracted only limited attention. Additionally, a discrepancy in the corrosion performance of LPBF printed 316L has been reported due to the complex microstructure and defects introduced during LPBF. Therefore, understanding the influence of processing parameters and feedstock on defects and microstructure becomes critical in understanding the processing-corrosion relationships and producing LPBF printed 316L components with reproducible properties. This review presents the influence of feedstock, processing parameters, and post-processing techniques on manufacturing defects, microstructure, and corrosion performance of LPBF printed 316L. Strategies and hypotheses to improve the corrosion resistance of LPBF printed 316L are also presented.}, journal={MATERIALS & DESIGN}, author={Vukkum, V. B. and Gupta, R. K.}, year={2022}, month={Sep} }
 @article{darwish_christudasjustus_witharamage_gupta_2022, title={Structure and Composition of the Passive Film Studied Using a Combination of X-Ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry, and Scanning Transmission Electron Microscopy}, url={https://doi.org/10.1149/MA2022-01161005mtgabs}, DOI={10.1149/MA2022-01161005mtgabs}, abstractNote={  	Characteristics of the passive film and the ability of an alloy to repassivate in any event of passive film breakdown control the corrosion. Studying the passive film has been of great interest since late 1836 when first-time iron was called altered iron. Significant progress in understanding the passive film composition and factors causing breakdown, pit growth and repassivation has been made over the past several decades. However, the role of metallurgical parameters on the passive film structure, composition, crystallinity, chloride ion interaction needs further research attention. The composition and structure of the passive film in Al alloys and stainless steels have been studied using advanced analytical techniques with high depth and spatial resolution have been presented herein. We have used a combination of time of flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron microscopy (XPS), and scanning transmission electron microscopy to study the passive film and pits. The surface film was studied after potentiostatic polarization as well as immersion tests in NaCl solution with immersion time varying from 30 minutes to four weeks. The crystallinity of the passive film was dependent on the composition and microstructure of the alloy. The incorporation of chloride and its distribution in the passive film was dependent on the material and conditions used to produce the passive film. The thickness of the passive film was found to depend on the microstructure of the underlying substrate. The role of the microstructure on passive film structure, breakdown, and repassivation or pit growth will be discussed.    }, journal={ECS Meeting Abstracts}, author={Darwish, Ahmed A and Christudasjustus, Jijo and Witharamage, Chathuranga S and Gupta, Rajeev Kumar}, year={2022}, month={Jul} }
 @article{christudasjustus_witharamage_walunj_borkar_gupta_2022, title={The influence of spark plasma sintering temperatures on the microstructure, hardness, and elastic modulus of the nanocrystalline Al-xV alloys produced by high-energy ball milling}, volume={122}, ISSN={["1005-0302"]}, url={https://doi.org/10.1016/j.jmst.2022.02.008}, DOI={10.1016/j.jmst.2022.02.008}, abstractNote={• Synthesis of Al-V alloys from high-energy ball milling and spark plasma sintering. • Al-V alloys with far-from-equilibrium microstructure: V solubility 6 orders of magnitude higher than equilibrium value. • Elastic modulus of Al-V alloys is much higher than that of any commercial Al alloy. • Effect of spark plasma sintering temperature on the microstructure, hardness and elastic modulus of Al-V alloys. Al- x V alloys ( x = 2 at.%, 5 at.%, 10 at.%) with nanocrystalline structure and high solid solubility of V were produced in powder form by high-energy ball milling (HEBM). The alloy powders were consolidated by spark plasma sintering (SPS) employing a wide range of temperatures ranging from 200 to 400 °C. The microstructure and solid solubility of V in Al were investigated using X-ray diffraction analysis, scanning electron microscope and transmission electron microscope. The microstructure was influenced by the SPS temperature and V content of the alloy. The alloys exhibited high solid solubility of V―six orders of magnitude higher than that in equilibrium state and grain size < 50 nm at all the SPS temperatures. The formation of Al 3 V intermetallic was detected at 400 °C. Formation of a V-lean phase and bimodal grain size was observed during SPS, which increased with the increase in SPS temperature. The hardness and elastic modulus, measured using nanoindentation, were significantly higher than commercial alloys. For example, Al-V alloy produced by SPS at 200 °C exhibited a hardness of 5.21 GPa along with elastic modulus of 96.21 GPa. The evolution of the microstructure and hardness with SPS temperatures has been discussed.}, journal={JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY}, publisher={Elsevier BV}, author={Christudasjustus, J. and Witharamage, C. S. and Walunj, Ganesh and Borkar, T. and Gupta, R. K.}, year={2022}, month={Sep}, pages={68–76} }
 @article{li_nash_o'brien_qiu_gupta_birbilis_2022, title={cardiGAN: A generative adversarial network model for design and discovery of multi principal element alloys}, volume={125}, ISSN={["1005-0302"]}, url={https://doi.org/10.1016/j.jmst.2022.03.008}, DOI={10.1016/j.jmst.2022.03.008}, abstractNote={• A generative model was developed for predicting and designing MPEAs. • The model presented herein, termed cardiGAN, was demonstrated as capable of functioning with high accuracy in performance. • The cardiGAN model may be utilized to generate large numbers of candidate MPEAs with minimal computational burden, generating novel compositions. Multi-principal element alloys (MPEAs), inclusive of high entropy alloys (HEAs), continue to attract significant research attention owing to their potentially desirable properties. Although MPEAs remain under extensive research, traditional (i.e. empirical) alloy production and testing are both costly and time-consuming, partly due to the inefficiency of the early discovery process which involves experiments on a large number of alloy compositions. It is intuitive to apply machine learning in the discovery of this novel class of materials, of which only a small number of potential alloys have been probed to date. In this work, a proof-of-concept is proposed, combining generative adversarial networks (GANs) with discriminative neural networks (NNs), to accelerate the exploration of novel MPEAs. By applying the GAN model herein, it was possible to directly generate novel compositions for MPEAs, and to predict their phases. To verify the predictability of the model, alloys designed by the model are presented and a candidate produced – as validation. This suggests that the model herein offers an approach that can significantly enhance the capacity and efficiency of development of novel MPEAs.}, journal={JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY}, author={Li, Z. and Nash, W. T. and O'Brien, S. P. and Qiu, Y. and Gupta, R. K. and Birbilis, N.}, year={2022}, month={Oct}, pages={81–96} }
 @article{o'brien_christudasjustus_esteves_vijayan_jinschek_birbilis_gupta_2021, title={A low-cost, low-density, and corrosion resistant AlFeMnSi compositionally complex alloy}, volume={5}, ISSN={["2397-2106"]}, url={https://doi.org/10.1038/s41529-021-00158-5}, DOI={10.1038/s41529-021-00158-5}, abstractNote={Abstract}, number={1}, journal={NPJ MATERIALS DEGRADATION}, publisher={Springer Science and Business Media LLC}, author={O'Brien, S. P. and Christudasjustus, J. and Esteves, L. and Vijayan, S. and Jinschek, J. R. and Birbilis, N. and Gupta, R. K.}, year={2021}, month={Mar} }
 @article{khan_larimian_borkar_gupta_2021, title={Corrosion Behavior and Hardness of Binary Mg Alloys Produced via High-Energy Ball-Milling and Subsequent Spark Plasma Sintering}, volume={77}, ISSN={["1938-159X"]}, DOI={10.5006/3633}, abstractNote={In this work, nine nanocrystalline binary Mg alloys were synthesized by high-energy ball milling. The compositions, Mg-5 wt% M (M-Cr, Ge, Mn, Mo, Ta, Ti, V, Y, and Zn), were milled with the objective of achieving non-equilibrium alloying. The milled alloys were consolidated via cold compaction (CC) at 25°C and spark plasma sintering (SPS) at 300°C. X-ray diffraction (XRD) analysis indicated grain refinement below 100 nm, and the scanning electron microscopy revealed homogeneous microstructures for all compositions. XRD analysis revealed that most of the alloys showed a change in the lattice parameter, which indicates the formation of a solid solution. A significant increase in the hardness compared to unmilled Mg was observed for all of the alloys. The corrosion behavior was improved in all of the binary alloys compared to milled Mg. A significant decrease in the cathodic kinetics was evident due to Ge and Zn additions. The influence of the alloying elements on corrosion behavior has been categorized and discussed based on the electrochemical response of their respective binary Mg alloys.}, number={2}, journal={CORROSION}, author={Khan, Mohammad Umar Farooq and Larimian, Taban and Borkar, T. and Gupta, R. K.}, year={2021}, month={Feb}, pages={228–241} }
 @article{esteves_witharamage_christudasjustus_walunj_o'brien_ryu_borkar_akans_gupta_2021, title={Corrosion behavior of AA5083 produced by high-energy ball milling}, volume={857}, ISSN={["1873-4669"]}, url={http://dx.doi.org/10.1016/j.jallcom.2020.158268}, DOI={10.1016/j.jallcom.2020.158268}, abstractNote={The corrosion, microstructure, and hardness of nanocrystalline AA5083 were compared to that of conventional AA5083-H116 and consolidated gas atomized powder. The nanocrystalline AA5083 was produced by consolidating high-energy ball milled gas atomized powder with two methods: cold compaction and spark plasma sintering. Electrochemical impedance spectroscopy, cyclic potentiodynamic polarization, Mott-Schottky analysis, and immersion tests followed by surface analysis were used to evaluate the corrosion behavior in 0.6 M NaCl solution. Pitting corrosion resistance of the nanocrystalline AA5083 was superior to that of commercial AA5083-H116. The improved corrosion resistance was primarily attributed to the homogenous microstructure and significant grain refinement below 100 nm.}, journal={JOURNAL OF ALLOYS AND COMPOUNDS}, publisher={Elsevier BV}, author={Esteves, L. and Witharamage, C. S. and Christudasjustus, J. and Walunj, G. and O'Brien, S. P. and Ryu, S. and Borkar, T. and Akans, R. E. and Gupta, R. K.}, year={2021}, month={Mar} }
 @article{esteves_christudasjustus_o'brien_witharamage_darwish_walunj_stack_borkar_akans_gupta_2021, title={Effect of V content on corrosion behavior of high-energy ball milled AA5083}, volume={186}, ISSN={["1879-0496"]}, url={https://doi.org/10.1016/j.corsci.2021.109465}, DOI={10.1016/j.corsci.2021.109465}, abstractNote={AA5083 alloys with V additions were produced in the powder form by high-energy ball milling and consolidation by spark plasma sintering and cold compaction. X-ray diffraction and energy dispersive X-ray spectroscopy analysis indicated the formation of supersaturated solid solution and grain refinement below 100 nm. Corrosion behavior was investigated using electrochemical impedance spectroscopy, cyclic potentiodynamic polarization, and immersion corrosion tests followed by surface analysis. The composition of the passive film was obtained via X-ray photoelectron spectroscopy. The corrosion resistance of the AA5083 was significantly improved due to the addition of V and high-energy ball milling.}, journal={CORROSION SCIENCE}, publisher={Elsevier BV}, author={Esteves, L. and Christudasjustus, J. and O'Brien, S. P. and Witharamage, C. S. and Darwish, A. A. and Walunj, G. and Stack, P. and Borkar, T. and Akans, R. E. and Gupta, R. K.}, year={2021}, month={Jul} }
 @article{patil_nartu_ozdemir_banerjee_gupta_borkar_2021, title={Enhancement of the mechanical properties of graphene nanoplatelet (GNP) reinforced nickel matrix nanocomposites}, volume={817}, ISSN={["1873-4936"]}, url={https://doi.org/10.1016/j.msea.2021.141324}, DOI={10.1016/j.msea.2021.141324}, abstractNote={The graphene nanoplatelet (GNP) reinforced nickel matrix composites (Ni-GNP) have been processed using two different ball milling approaches, viz, dry ball milling (DM) and solution ball milling (SBM), followed by consolidation using spark plasma sintering (SPS) technique. The composites were reinforced with varying GNP concentration (0.5–2 wt%) and were milled for up to 12 hr to investigate the effect of premixing technique, milling duration, and GNP concentration on the grain size, microstructure, the dispersion of GNP in the nickel matrix, and mechanical behavior of these composites. Ni-GNP nanocomposites exhibited improved microhardness and tensile strength compared to pure nickel, primarily attributed to grain refinement and load transfer strengthening due to the uniform dispersion of these GNPs within the nickel matrix, promoting effective load transfer during tensile deformation. Ni-0.5GNP composites processed via dry milling followed by SPS exhibited the highest tensile yield strength of 586 MPa as compared to pure nickel and other Ni-GNP composites. The contribution of each strengthening mechanism in the overall improvement in yield strength of Ni-GNP composites has been qualitatively calculated/quantified and compared with experimentally obtained tensile properties.}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, publisher={Elsevier BV}, author={Patil, Amit and Nartu, Mohan Sai Kiran Kumar Yadav and Ozdemir, Furkan and Banerjee, Raj and Gupta, Rajeev Kumar and Borkar, Tushar}, year={2021}, month={Jun} }
 @article{daroonparvar_kasar_farooq khan_l. menezes_kay_misra_gupta_2021, title={Improvement of Wear, Pitting Corrosion Resistance and Repassivation Ability of Mg-Based Alloys Using High Pressure Cold Sprayed (HPCS) Commercially Pure-Titanium Coatings}, volume={11}, ISSN={["2079-6412"]}, url={https://doi.org/10.3390/coatings11010057}, DOI={10.3390/coatings11010057}, abstractNote={In this study, a compact cold sprayed (CS) Ti coating was deposited on Mg alloy using a high pressure cold spray (HPCS) system. The wear and corrosion behavior of the CS Ti coating was compared with that of CS Al coating and bare Mg alloy. The Ti coating yielded lower wear rate compared to Al coating and Mg alloy. Electrochemical impedance spectroscopy (EIS) and cyclic potentiodynamic polarization (CPP) tests revealed that CS Ti coating can substantially reduce corrosion rate of AZ31B in chloride containing solutions compared to CS Al coating. Interestingly, Ti-coated Mg alloy demonstrated negative hysteresis loop, depicting repassivation of pits, in contrast to AZ31B and Al-coated AZ31B with positive hysteresis loops where corrosion potential (Ecorr) > repassivation potential (Erp); indicating irreversible growth of pits. AZ31B and Al-coated AZ31B were most susceptible to pitting corrosion, while Ti-coated Mg alloy indicated noticeable resistance to pitting in 3.5 wt % NaCl solution. In comparison to Al coating, Ti coating considerably separated the AZ31BMg alloy surface from the corrosive electrolyte during long term immersion test for 11 days.}, number={1}, journal={COATINGS}, publisher={MDPI AG}, author={Daroonparvar, Mohammadreza and Kasar, Ashish K. and Farooq Khan, Mohammad Umar and L. Menezes, Pradeep and Kay, Charles M. and Misra, Manoranjan and Gupta, Rajeev K.}, year={2021}, month={Jan} }
 @article{choudhary_s. o'brien_qiu_thomas_gupta_birbilis_2021, title={On the dynamic passivity and corrosion resistance of a low cost and low density multi-principal-element alloy produced via commodity metals}, volume={125}, ISBN={1873-1902}, DOI={10.1016/j.elecom.2021.106989}, abstractNote={Recent exploration of multi-principal-element alloys (MPEAs), which include the so-called high-entropy alloys, has revealed hitherto unreported properties and phenomena arising from investigation of broader compositional space. Herein, a low cost and lightweight alloy (equiatomic AlFeMnSi) is presented that exhibits exceptional corrosion resistance in 0.6 M NaCl solution, despite a multiphase structure and the absence of well-known passivating elements (such as Cr, Mo, Ti and Nb). In-line inductively-coupled plasma mass spectroscopy (ICP-MS) analysis of alloy dissolution and angle-resolved X-ray photoelectron spectroscopy (AR-XPS) of the surface film revealed that the alloy passivates by a unique mechanism involving dissolution–precipitation of Si. The dynamic precipitation of a Si hydroxide surface film results in excellent passivity of the alloy, revealing the possibility of developing low-cost corrosion-resistant alloys from metals available from waste streams.}, journal={ELECTROCHEMISTRY COMMUNICATIONS}, author={Choudhary, S. and S. O'Brien and Qiu, Y. and Thomas, S. and Gupta, R. K. and Birbilis, N.}, year={2021}, month={Apr} }
 @article{liu_li_liu_ma_du_chen_zhang_gupta_chen_zhang_2021, title={Sluggish precipitation strengthening in Al-Li alloy with a high concentration of Mg}, volume={11}, ISSN={["2214-0697"]}, url={https://doi.org/10.1016/j.jmrt.2021.02.037}, DOI={10.1016/j.jmrt.2021.02.037}, abstractNote={The influence of different Mg concentrations on the mechanical properties and microstructure of an Al–Li alloy was studied. The highest Mg content was up to 1.1 wt.%. To the best of the authors knowledge, alloys with such a high Mg content has not been reported in the literature. The mechanical properties, yield strength and elongation at failure, of all of the alloys were investigated by tensile tests. Characterisation of the precipitates by analysing the dark field images and related diffraction patterns revealed that precipitation of the T1 phase (Al2CuLi) was retarded by high (1.1 wt.%) Mg concentration. We hypothesized that a competition between the precipitation of T1 phase and S' phase in high Mg containing alloy caused sluggish precipitation phenomenon and associated strengthening.}, journal={JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T}, publisher={Elsevier BV}, author={Liu, Zhen-zhen and Li, Jin-feng and Liu, Dan-yang and Ma, Yun-long and Du, Yue and Chen, Yong-lai and Zhang, Xu-hu and Gupta, Rajeev Kumar and Chen, Xiaobo and Zhang, Rui-feng}, year={2021}, pages={1806–1815} }
 @article{larimian_chaudhary_khan_ramanujan_gupta_borkar_2021, title={Spark plasma sintering of Fe–Si–B–Cu–Nb / Finemet based alloys}, volume={129}, ISSN={0966-9795}, url={http://dx.doi.org/10.1016/j.intermet.2020.107035}, DOI={10.1016/j.intermet.2020.107035}, abstractNote={The influence of mechanical alloying (MA) and spark plasma sintering (SPS) processing parameters on the microstructure, magnetic and mechanical properties of Finemet (Fe73.5Cu1Nb3Si13.5B9) type alloys was investigated. Finemet alloy powder was obtained via mechanical alloying of elemental powders for 30 h, 60 h, 90 h, and 120 h with ball to powder ratio (BPR) of 10:1 and 15:1. The milled powders were consolidated using the SPS process. The XRD patterns confirm the presence of the α-Fe3Si phase in all Finemet alloys, also broadening of the (110) peak of α-Fe3Si was observed with increasing milling time. The microhardness of Finemet alloys increases with increase in milling time primarily due to a decrease in grain size. All samples show good saturation magnetization (Ms), 120h sample exhibiting the highest Ms of 166 emu/g, however coercivity increases with increasing milling time. Additionally, α-Fe3Si crystal size decreases with increasing the BPR primarily due to higher impact energy.}, journal={Intermetallics}, publisher={Elsevier BV}, author={Larimian, T. and Chaudhary, V. and Khan, M.U.F. and Ramanujan, R.V. and Gupta, R.K. and Borkar, T.}, year={2021}, month={Feb}, pages={107035} }
 @article{patil_nartu_ozdemir_banerjee_gupta_borkar_2021, title={Strengthening effects of multi-walled carbon nanotubes reinforced nickel matrix nanocomposites}, volume={876}, ISSN={["1873-4669"]}, url={https://doi.org/10.1016/j.jallcom.2021.159981}, DOI={10.1016/j.jallcom.2021.159981}, abstractNote={The multi-walled carbon nanotubes (CNTs) reinforced nickel matrix nanocomposites (Ni-CNT) have been processed via ball milling followed by spark plasma sintering (SPS) process. The CNT content in these nanocomposites has been varied from 0.5 to 2 wt% (approximately from 2 to 8 vol%) to study their effect on the dispersion, microstructure, and mechanical behavior of these composites. Two Ni-CNT composite powders pre-mixing techniques have been employed, namely dry milling (DM) and solution ball milling (SBM), to investigate their effect on the dispersion of CNTs within a nickel matrix. The Ni-CNT powder was milled for different durations (1,2,6 and 12 hrs.) to investigate the milling effect on the grain size and the dispersion of CNTs in the nickel matrix. Ni-CNT nanocomposites exhibited improvement in microhardness and mechanical performance in comparison with pure nickel. Ni-1CNT-DM composites exhibited an excellent combination of the tensile yield strength of 455 MPa and around 13% elongation. This improvement in Ni-CNT nanocomposites is primarily attributed to the uniform dispersion of reinforcement within the nickel matrix, refined grain size, and strong nickel CNT interfacial bonding, which effectively transfers stress during tensile deformation. Various strengthening mechanisms associated with CNT-metal matrix composites have been discussed in detail. We have attempted to quantify the contribution of these strengthening mechanisms using micromechanical models.}, journal={JOURNAL OF ALLOYS AND COMPOUNDS}, publisher={Elsevier BV}, author={Patil, Amit and Nartu, Mohan Sai Kiran Kumar Yadav and Ozdemir, Furkan and Banerjee, Raj and Gupta, Rajeev Kumar and Borkar, Tushar}, year={2021}, month={Sep} }
 @article{witharamage_christudasjustus_gupta_2021, title={The Effect of Milling Time and Speed on Solid Solubility, Grain Size, and Hardness of Al-V Alloys}, volume={30}, ISSN={["1544-1024"]}, url={https://doi.org/10.1007/s11665-021-05663-x}, DOI={10.1007/s11665-021-05663-x}, number={4}, journal={JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE}, publisher={Springer Science and Business Media LLC}, author={Witharamage, C. S. and Christudasjustus, J. and Gupta, R. K.}, year={2021}, month={Apr}, pages={3144–3158} }
 @inbook{walunj_bearden_patil_larimian_christudasjustus_gupta_borkar_2021, place={Cham, Switzerland}, title={The Effect of Titanium Carbide and Spark Plasma Sintering Processing on Nickel–Titanium Carbide Composites}, ISBN={9783030652494}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85102048699&partnerID=MN8TOARS}, DOI={10.1007/978-3-030-65249-4_4}, abstractNote={The influence of variations in the titanium carbide (TiC) content employed during spark plasma sintering (SPS) of nickel–titanium carbide (Ni-TiC) composites on its microstructure and mechanical properties has been investigated systematically. Mechanical alloying (MA) uses a technique of cold welding and repetitive fracturing of composite powder to make homogenous alloys powder. The SPS consolidates alloy powder into dense samples using joule heating at a lower temperature. Mechanical alloying was performed using a planetary high energy ball mill with 400 rpm and ball to powder ratio 15:1 for 24 h. Bulk Ni-TiC composites (with TiC content varying from 5 to 25 wt.%) consolidated via mechanical alloying followed by SPS at 65 MPa pressure and 900 °C temperature. All consolidated Ni-TiC samples exhibit significant improvement in microhardness, compression strength, and grain size due to the addition of titanium carbide (TiC) particles. The grain size of Ni reduces to approx. 40 nm from approx. 55 nm. The microhardness increases from 294 to 483 HV by increasing the weight percentage of TiC from 5 to 25.}, booktitle={Metal-Matrix Composites: Advances in Analysis, Measurement, and Observations}, publisher={Springer Nature}, author={Walunj, G. and Bearden, A. and Patil, A. and Larimian, T. and Christudasjustus, J. and Gupta, R.K. and Borkar, T.}, editor={Srivatsan, T.S. and Harrigan, W.C., Jr/ and Hunyadi Murph, S.Editors}, year={2021}, pages={65–73} }
 @article{patil_walunj_ozdemir_gupta_borkar_2021, title={Tribological Behavior of Carbon-Based Nanomaterial-Reinforced Nickel Metal Matrix Composites}, volume={14}, ISSN={["1996-1944"]}, url={https://doi.org/10.3390/ma14133536}, DOI={10.3390/ma14133536}, abstractNote={Carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) with exceptional mechanical, thermal, chemical, and electrical properties are enticing reinforcements for fabricating lightweight, high-strength, and wear-resistant metal matrix composites with superior mechanical and tribological performance. Nickel–carbon nanotube composite (Ni-CNT) and nickel–graphene nanoplatelet composite (Ni-GNP) were fabricated via mechanical milling followed by the spark plasma sintering (SPS) technique. The Ni-CNT/GNP composites with varying reinforcement concentrations (0.5, 2, and 5 wt%) were ball milled for twelve hours to explore the effect of reinforcement concentration and its dispersion in the nickel microstructure. The effect of varying CNT/GNP concentration on the microhardness and the tribological behavior was investigated and compared with SPS processed monolithic nickel. Ball-on-disc tribological tests were performed to determine the effect of different structural morphologies of CNTs and GNPs on the wear performance and coefficient of friction of these composites. Experimental results indicate considerable grain refinement and improvement in the microhardness of these composites after the addition of CNTs/GNPs in the nickel matrix. In addition, the CNTs and GNPs were effective in forming a lubricant layer, enhancing the wear resistance and lowering the coefficient of friction during the sliding wear test, in contrast to the pure nickel counterpart. Pure nickel demonstrated the highest CoF of ~0.9, Ni-0.5CNT and Ni-0.5GNP exhibited a CoF of ~0.8, whereas the lowest CoF of ~0.2 was observed for Ni-2CNT and Ni-5GNP composites. It was also observed that the uncertainty of wear resistance and CoF in both the CNT/GNP-reinforced composites increased when loaded with higher reinforcement concentrations. The wear surface was analyzed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analysis to elucidate the wear mechanism in these composites.}, number={13}, journal={MATERIALS}, author={Patil, Amit and Walunj, Ganesh and Ozdemir, Furkan and Gupta, Rajeev Kumar and Borkar, Tushar}, year={2021}, month={Jul} }
 @article{patil_walunj_torgerson_koricherla_khan_scharf_gupta_borkar_2021, title={Tribological Behavior of In Situ Processed Ni-Ti-C Nanocomposites}, volume={64}, url={https://doi.org/10.1080/10402004.2020.1800880}, DOI={10.1080/10402004.2020.1800880}, abstractNote={Abstract Ni-Ti-C metal matrix composites (MMCs) with in situ formed, homogeneously distributed titanium carbide (TiC), as well as graphite (C) reinforcement in the nickel metal matrix, were synthesized using mechanical alloying (MA) followed by spark plasma sintering (SPS). The main objective of this research is to consolidate Ni-Ti-C MMCs with varying C/Ti ratio and characterize the MMCs to investigate the altered mechanical and tribological behavior in comparison with pure nickel. Experimental results showed that these composites possess a refined microstructure in addition to the presence of hard TiC precipitates within the nickel matrix. Additionally, by tailoring the C/Ti ratio in these composites, an additional graphitic phase is engineered into the microstructure. All Ni-Ti-C nanocomposites exhibited excellent microhardness as well as enhanced tribological performance compared to pure nickel. The increased mechanical properties are primarily attributed to the presence of in situ formed nanoscopic TiC and graphite reinforcing the nickel matrix.}, number={1}, journal={Tribology Transactions}, publisher={Informa UK Limited}, author={Patil, Amit and Walunj, Ganesh and Torgerson, Tyler B. and Koricherla, Manindra V. and Khan, Mohammed U. F. and Scharf, Thomas W. and Gupta, Rajeev and Borkar, Tushar}, year={2021}, month={Jan}, pages={53–64} }
 @article{o'brien_esteves_birbilis_gupta_2020, title={A low-cost, low-density and corrosion resistant compositionally complex alloy: AlFeMnSi}, volume={1}, url={https://doi.org/10.1149/osf.io/ew86m}, DOI={10.1149/osf.io/ew86m}, abstractNote={A new class of compositionally complex alloy, consisting of equiatomic concentrations of Al, Fe, Mn and Si is reported. The alloy was characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Corrosion behavior of the AlFeMnSi alloy, as evaluated using potentiodynamic polarization tests and electrochemical impedance spectroscopy in 0.6 M NaCl solution, was comparable with that of stainless steel (SS) 304L. X-ray photoelectron spectroscopy was used to study the AlFeMnSi surface film. The AlFeMnSi alloy also exhibited a lower cost, lower density, and a higher hardness as compared with SS 304L, rendering it a promising alloy for bespoke applications.}, publisher={The Electrochemical Society}, author={O'Brien, Sean and Esteves, Luiza and Birbilis, Nick and Gupta, Rajeev}, year={2020}, month={Jan} }
 @article{larimian_chaudhary_christudasjustus_ramanujan_gupta_borkar_2020, title={Bulk-nano spark plasma sintered Fe-Si-B-Cu-Nb based magnetic alloys}, volume={124}, ISSN={0966-9795}, url={http://dx.doi.org/10.1016/j.intermet.2020.106869}, DOI={10.1016/j.intermet.2020.106869}, abstractNote={Iron-based soft magnetic alloys (FeSiB, FeSiBNb, FeSiBCu, and FeSiBNbCu (Finemet)) have been fabricated via mechanical alloying followed by spark plasma sintering (SPS) process. FeSiB alloy powder was obtained by high energy ball milling of an elemental blend Fe, Si, and B powders. The effect of milling time on crystallite size and phase transformation was studied. Additionally, FeSiBCu, FeSiBNb, and FeSiBCuNb alloy powders were milled to study the effect of Cu and Nb on phase transformation, mechanical, and magnetic behavior. The mechanically alloyed powders were sintered via SPS process to achieve full densification. The microhardness and magnetic permeability of sintered FeSiB alloys were found to be increased monotonically with milling time primarily due to the smaller crystallite size and more uniform microstructure. Interestingly, the alloying of Cu or (and) Nb to FeSiB resulted in higher saturation magnetization and lower coercivity mainly due to large volume fraction of α-Fe3Si nanocrystals. Overall, these alloys exhibit reasonably good soft magnetic behavior along with excellent microhardness. Mechanical alloying followed by spark plasma sintering opens up a new avenue of processing amorphous-nanocrystalline alloys into bulk shape with good mechanical and magnetic properties.}, journal={Intermetallics}, publisher={Elsevier BV}, author={Larimian, T. and Chaudhary, V. and Christudasjustus, J. and Ramanujan, R.V. and Gupta, R. and Borkar, T.}, year={2020}, month={Sep}, pages={106869} }
 @article{daroonparvar_farooq khan_saadeh_kay_gupta_kasar_kumar_misra_menezes_bakhsheshi-rad_2020, title={Enhanced corrosion resistance and surface bioactivity of AZ31B Mg alloy by high pressure cold sprayed monolayer Ti and bilayer Ta/Ti coatings in simulated body fluid}, volume={256}, ISSN={0254-0584}, url={http://dx.doi.org/10.1016/j.matchemphys.2020.123627}, DOI={10.1016/j.matchemphys.2020.123627}, abstractNote={Ti and Ta/Ti coatings were successfully applied on AZ31B Mg alloy using high pressure cold spray process. These coatings (particularly Ta/Ti coating) with high hardness lowered the wear rate of AZ31BMg alloy. In-vitro bioactivity test, infinite focus 3D measurement and EDS results revealed that the calcium-phosphate (Ca–P) compounds nucleation and growth capabilities on both the coatings surface are higher than AZ31B Mg alloy surface due to the highly passivating nature and rough surface (island-like) of the high pressure cold sprayed Ti and Ta/Ti coatings, which are further conducive to the biological fixation. Electrochemical corrosion and immersion tests disclosed that a dense layer of Ta on Ti coating was able to enhance the corrosion resistance of Ti/AZ31B Mg system in the Hank's balanced salt solution. Rct (charge transfer resistance) and │Z│f=0.01Hz values for Ta/Ti coated Mg alloy have remained slightly stable. This imparted that the rate of electrochemical processes at the electrode/electrolyte interface could remain very slow in the course of immersion time. Likewise, the OCP (open circuit potential) values of Ta/Ti coating remained constant during long term electrochemical corrosion test. This behavior could originate from fairly dense structure of the high pressure cold sprayed Ta layer which considerably impeded the penetration of corrosive solution into the coating interiors. Ta/Ti coating presented the most positive potential, highest Rct, and highest│Z│f=0.01Hz values, suggesting that it is the most thermodynamically stable/least to be corroded in Hank's balanced salt solution over time. In general, cold sprayed Ta/Ti coating might open a new way to broaden the utilization of Mg alloys in the field of biomaterials.}, journal={Materials Chemistry and Physics}, publisher={Elsevier BV}, author={Daroonparvar, M. and Farooq Khan, M.U. and Saadeh, Y. and Kay, C.M. and Gupta, R.K. and Kasar, A.K. and Kumar, P. and Misra, M. and Menezes, Pradeep L. and Bakhsheshi-Rad, H.R.}, year={2020}, month={Dec}, pages={123627} }
 @article{rashidi_choi_stevenson_pandey_gupta_2020, title={High temperature oxidation behavior of aluminized Haynes 230}, volume={174}, ISSN={0010-938X}, url={http://dx.doi.org/10.1016/j.corsci.2020.108835}, DOI={10.1016/j.corsci.2020.108835}, abstractNote={The effect of reactive air aluminizing (RAA) on the high temperature oxidation behavior of the H230 superalloy is studied at 850 °C for 600 h. Mass gain values are measured and microstructure is studied by XRD, SEM, and EDX. Post oxidation mass gain for the aluminized H230 is reduced compared to wrought H230. The RAA process lead to formation of a three-zone diffusion coating with dominant β-NiAl in the two outer zones and increased γ'-Ni3Al after high temperature oxidation, which is attributed to the alumina scale growth during the high temperature oxidation.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Rashidi, S. and Choi, J.P. and Stevenson, J.W. and Pandey, A. and Gupta, R.K.}, year={2020}, month={Sep}, pages={108835} }
 @article{ress_martin_bosch_gupta_bastidas_2020, title={Intergranular to Intragranular Pitting Corrosion Transition Mechanism of Sensitized AA5083 at 150 °C}, volume={10}, url={https://doi.org/10.3390/met10081082}, DOI={10.3390/met10081082}, abstractNote={Intergranular corrosion (IGC) and pitting transition caused by grain boundary β-phase saturation of aluminum alloy AA5083 sensitized at 150 °C was investigated in 3.5 wt% NaCl solution. The change in the localized corrosion mechanism from IGC to pitting was studied by microstructural and electrochemical analysis, where IGC was found to be the primary mechanism at low degrees of sensitization (DoS) and pitting corrosion was observed to develop after grain boundary β-phase saturation. Evaluation of the double layer capacitance by electrochemical impedance spectroscopy (EIS) and charge passed through the specimens by potentiostatic current monitoring demonstrated a well differentiated three-stage dissolution mechanism.}, number={8}, journal={Metals}, publisher={MDPI AG}, author={Ress, Jacob and Martin, Ulises and Bosch, Juan and Gupta, Rajeev K. and Bastidas, David M.}, year={2020}, month={Aug}, pages={1082} }
 @article{walunj_bearden_patil_larimian_christudasjustus_gupta_borkar_2020, title={Mechanical and Tribological Behavior of Mechanically Alloyed Ni-TiC Composites Processed via Spark Plasma Sintering}, volume={13}, ISSN={["1996-1944"]}, url={https://doi.org/10.3390/ma13225306}, DOI={10.3390/ma13225306}, abstractNote={Titanium carbide (TiC) reinforced nickel (Ni) matrix composites were processed via mechanical alloying (MA) followed by spark plasma sintering (SPS) process. Mechanical alloying has gained special attention as a powerful non-equilibrium process for fabricating amorphous and nanocrystalline materials, whereas spark plasma sintering (SPS) is a unique technique for processing dense and near net shape bulk alloys with homogenous microstructure. TiC reinforcement varied from 5 to 50 wt.% into nickel matrix to investigate its effect on the microstructure and mechanical behavior of Ni-TiC composites. All Ni-TiC composites powder was mechanically alloyed using planetary high energy ball mill with 400 rpm and ball to powder ratio (BPR) 15:1 for 24 h. Bulk Ni-TiC composites were then sintered via SPS process at 50 MPa pressure and 900–1200 °C temperature. All Ni-TiC composites exhibited higher microhardness and compressive strength than pure nickel due to the presence of homogeneously distributed TiC particles within the nickel matrix, matrix grain refinement, and excellent interfacial bonding between nickel and TiC reinforcement. There is an increase in Ni-TiC composites microhardness with an increase in TiC reinforcement from 5 to 50 wt.%, and it reaches the maximum value of 900 HV for Ni-50TiC composites.}, number={22}, journal={MATERIALS}, publisher={MDPI AG}, author={Walunj, Ganesh and Bearden, Anthony and Patil, Amit and Larimian, Taban and Christudasjustus, Jijo and Gupta, Rajeev Kumar and Borkar, Tushar}, year={2020}, month={Nov} }
 @article{daroonparvar_khan_saadeh_kay_kasar_kumar_esteves_misra_menezes_kalvala_et al._2020, title={Modification of surface hardness, wear resistance and corrosion resistance of cold spray Al coated AZ31B Mg alloy using cold spray double layered Ta/Ti coating in 3.5 wt % NaCl solution}, volume={176}, ISSN={0010-938X}, url={http://dx.doi.org/10.1016/j.corsci.2020.109029}, DOI={10.1016/j.corsci.2020.109029}, abstractNote={In this research, cold sprayed Al coating layer on AZ31B Mg alloy was coated with cold sprayed Ti and Ta/Ti coatings, which noticeably reduced the wear rate of Al coated Mg alloy. Electrochemical corrosion tests and infinite focus 3D measurement results revealed that the high surface activity of commercially pure-Al coating, diffusion-controlled reactions, and formation of corrosion pits could be mitigated using Ti top coating. However, a dense layer of Ta on Ti coating exceptionally improved the corrosion resistance of Ti/Al coated AZ31B Mg alloy in neutral 3.5 wt.% NaCl solution This work gives a new strategy to considerably raise the wear and corrosion resistances of cold spray Al coated Mg alloys by double layered Ta/Ti coatings.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Daroonparvar, M. and Khan, M.U. Farooq and Saadeh, Y. and Kay, C.M. and Kasar, A.K. and Kumar, P. and Esteves, L. and Misra, M. and Menezes, P. and Kalvala, P.R. and et al.}, year={2020}, month={Nov}, pages={109029} }
 @article{esquivel_gupta_2020, title={Review—Corrosion-Resistant Metastable Al Alloys: An Overview of Corrosion Mechanisms}, volume={167}, url={https://doi.org/10.1149/1945-7111/ab8a97}, DOI={10.1149/1945-7111/ab8a97}, abstractNote={Commercial aluminum alloys exhibit localized corrosion when exposed to environments containing aggressive anions. Alloying of Al with specific elements (M: Cr, Mo, V, Nb, etc) using non-equilibrium processing techniques has been reported to result in significantly improved corrosion resistance due to the formation of a supersaturated solid solution and uniform distribution of M in the matrix. Several theories describing the corrosion behavior of Al–M alloys have been postulated. This paper presents an overview of the most common non-equilibrium alloying techniques implemented for the production of the metastable Al–M alloys and posited corrosion mechanisms for the improved corrosion resistance.}, number={8}, journal={Journal of The Electrochemical Society}, publisher={The Electrochemical Society}, author={Esquivel, J. and Gupta, R. K.}, year={2020}, month={Jan}, pages={081504} }
 @article{khan_patil_christudasjustus_borkar_gupta_2020, title={Spark plasma sintering of a high-energy ball milled Mg-10 wt% Al alloy}, volume={8}, url={https://doi.org/10.1016/j.jma.2020.02.006}, DOI={10.1016/j.jma.2020.02.006}, abstractNote={The influence of spark plasma sintering (SPS) temperature on microstructure, hardness and corrosion behavior of a high-energy ball milled Mg-10 wt% Al alloy was investigated in this work. The holding time and sintering pressure for SPS were kept constant while varying the sintering temperature from 200 to 350 °C. The grain size and microstructure were studied using X-ray diffraction analysis, scanning electron microscopy, energy dispersive X-ray spectroscopy, and Archimedes' based density measurement. Corrosion behavior was investigated using potentiodynamic polarization tests. The nanocrystalline regime (grain size < 100 nm) was maintained even after SPS up to 350 °C. The density of the alloy increased with increasing the SPS temperature. Vickers' hardness and corrosion performance improved up to 300 °C followed by a decrease after SPS at 350 °C. Possible reasons for densification, strengthening, and corrosion behavior have been discussed in the light of reduced porosity and microstructural changes.}, number={2}, journal={Journal of Magnesium and Alloys}, publisher={Elsevier BV}, author={Khan, M.U.F. and Patil, A. and Christudasjustus, J. and Borkar, T. and Gupta, R.K.}, year={2020}, month={Jun}, pages={319–328} }
 @article{daroonparvar_mat yajid_bakhsheshi-rad_gupta_ismail_2020, title={Study of Corrosion Behavior and In Vitro Bioactivity of Single NbSi2 and Duplex NbSi2/Nb5Si3 Coatings on Nb Substrates for Biomedical Applications}, volume={56}, ISSN={2070-2051 2070-206X}, url={http://dx.doi.org/10.1134/s2070205120030120}, DOI={10.1134/s2070205120030120}, number={3}, journal={Protection of Metals and Physical Chemistry of Surfaces}, publisher={Pleiades Publishing Ltd}, author={Daroonparvar, Mohammadreza and Mat Yajid, Muhamad Azizi and Bakhsheshi-Rad, Hamid Reza and Gupta, Rajeev Kumar and Ismail, A. F.}, year={2020}, month={May}, pages={628–637} }
 @article{rashidi_choi_stevenson_pandey_gupta_2019, title={Effect of Aluminizing on the High-Temperature Oxidation Behavior of an Alumina-Forming Austenitic Stainless Steel}, volume={71}, url={https://doi.org/10.1007/s11837-018-3155-y}, DOI={10.1007/s11837-018-3155-y}, number={1}, journal={JOM}, publisher={Springer Nature}, author={Rashidi, S. and Choi, J. P. and Stevenson, J. W. and Pandey, A. and Gupta, R. K.}, year={2019}, month={Jan}, pages={109–115} }
 @article{mavros_larimian_esqivel_gupta_contieri_borkar_2019, title={Spark plasma sintering of low modulus titanium-niobium-tantalum-zirconium (TNTZ) alloy for biomedical applications}, volume={183}, ISSN={0264-1275}, url={http://dx.doi.org/10.1016/j.matdes.2019.108163}, DOI={10.1016/j.matdes.2019.108163}, abstractNote={In metallurgy, titanium has been a staple for biomedical purposes. Its slow toxicity and alloying versatility make it an attractive choice for medical applications. However, studies have shown the difference in elastic modulus between titanium alloys (116 GPa) and human bone (10–40 GPa), which contributes to long term issues with loose hardware fixation. Additionally, long term studies have shown elements such as vanadium and aluminum, which are commonly used in Ti-6Al-4V biomedical alloys, have been linked to neurodegenerative diseases like Alzheimer and Parkinson. Alternative metals known to be less toxic are being explored as replacements for alloying elements in titanium alloys. This study will focus on advanced processing and characterization of β-phase titanium alloys for biomedical applications. The microstructure, mechanical, and electrochemical properties of these alloys have been analyzed and compared with C.P. titanium. Bond order B¯O and energy level M¯D approach has been used to design these alloys in order to achieve low elastic modulus. The main objective is to study the effect of different alloying elements on microstructure, phase transformation and mechanical properties of these newly developed low modulus β-phase titanium alloys and establish new avenues for the future development of biocompatible titanium alloys with optimum microstructure and properties.}, journal={Materials & Design}, publisher={Elsevier BV}, author={Mavros, Nicholas and Larimian, Taban and Esqivel, Javier and Gupta, Rajeev Kumar and Contieri, Rodrigo and Borkar, Tushar}, year={2019}, month={Dec}, pages={108163} }
 @article{qiu_thomas_gupta_gengenbach_jones_birbilis_2018, title={A Surface Study of the Native Oxide upon a Compositionally Complex Alloy}, volume={74}, ISSN={0010-9312 1938-159X}, url={http://dx.doi.org/10.5006/2967}, DOI={10.5006/2967}, abstractNote={The native surface oxide upon a single phase low-density compositionally complex alloy (CCA), AlTiVCr, was studied herein—owing to its exceptionally high aqueous corrosion resistance. The nature of the native surface oxide/surface film was elaborated in the context of corrosion resistance, based on results from electrochemical testing, secondary ion mass spectroscopy, and x-ray photoelectron spectroscopy. Selective oxidation and unoxidized metal in the surface film were observed. Such features are comparatively unique and posited to be relevant to CCAs and high entropy alloys more generally.}, number={12}, journal={CORROSION}, publisher={NACE International}, author={Qiu, Y. and Thomas, S. and Gupta, R.K. and Gengenbach, T. and Jones, R. and Birbilis, N.}, year={2018}, month={Oct}, pages={1312–1317} }
 @article{liu_li_ma_gupta_birbilis_zhang_2018, title={A closer look at the role of Zn in the microstructure and corrosion of an Al-Cu-Li alloy}, volume={145}, ISSN={0010-938X}, url={http://dx.doi.org/10.1016/j.corsci.2018.10.003}, DOI={10.1016/j.corsci.2018.10.003}, abstractNote={The influence of various amounts of Zn addition on the microstructure and associated intergranular corrosion of Al-2.8Cu-1.7Li-0.4Mg-0.3Mn-0.12Zr alloys was studied using transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy, and corrosion and electrochemical techniques. The added Zn was incorporated into the precipitates at the grain boundaries (GBs). Three types of phases at the GBs were confirmed. The quantity and space of the coarse phases at the GBs were related to Zn addition. The Zn addition decreased the potential difference between the conversed coarse phase (containing Zn) and the adjacent matrix, which improved the intergranular corrosion resistance.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Liu, D.Y. and Li, J.F. and Ma, Y.L. and Gupta, R.K. and Birbilis, N. and Zhang, R.}, year={2018}, month={Dec}, pages={220–231} }
 @article{daroonparvar_mat yajid_gupta_mohd yusof_bakhsheshi rad_ghandvar_ghasemi_2018, title={Antibacterial activities and corrosion behavior of novel PEO/nanostructured ZrO2 coating on Mg alloy}, volume={28}, ISSN={1003-6326}, url={http://dx.doi.org/10.1016/s1003-6326(18)64799-5}, DOI={10.1016/s1003-6326(18)64799-5}, abstractNote={Plasma electrolytic oxidation (PEO) was developed as a bond coat for air plasma sprayed (APS) nanostructure ZrO2 as top coat to enhance the corrosion resistance and antibacterial activity of Mg alloy. Corrosion behavior and antibacterial activities of coated and uncoated samples were assessed by electrochemical tests and agar diffusion method toward Escherichia coli (E. coli) bacterial pathogens, respectively. The lowest corrosion current density and the highest charge transfer resistance, phase angle and impedance modulus were observed for PEO/nano-ZrO2 coated sample compared with those of PEO coated and bare Mg alloys. Nano-ZrO2 top coat which has completely sealed PEO bond coat is able to considerably delay aggressive ions transportation towards Mg alloy surface and significantly enhances corrosion resistance of Mg alloy in simulated body fluid (SBF) solution. Moreover, higher antibacterial activity was also observed in PEO/nano-ZrO2 coating against bacterial strains than that of the PEO coated and bare Mg alloys. This observation was attributed to the presence of ZrO2 nanoparticles which decelerate E. coli growth as a result of E. coli membranes.}, number={8}, journal={Transactions of Nonferrous Metals Society of China}, publisher={Elsevier BV}, author={Daroonparvar, Mohammadreza and Mat Yajid, Muhamad Azizi and Gupta, Rajeev Kumar and Mohd Yusof, Noordin and Bakhsheshi Rad, Hamid Reza and Ghandvar, Hamidreza and Ghasemi, Ehsan}, year={2018}, month={Aug}, pages={1571–1581} }
 @article{huang_li_liu_zhang_chen_zhang_ma_gupta_birbilis_2018, title={Correlation of intergranular corrosion behaviour with microstructure in Al-Cu-Li alloy}, volume={139}, ISSN={0010-938X}, url={http://dx.doi.org/10.1016/j.corsci.2018.05.011}, DOI={10.1016/j.corsci.2018.05.011}, abstractNote={The IGC behaviour, OCP and microstructure of AA1460 (Al-3.12Cu-2.14Li-0.12Sc-0.12Zr, in wt.%), following HT1 (heat treatment without predeformation) and HT2 (heat treatment with predeformation) tempers were investigated. Both δ′ (Al3Li) and T1 (Al2CuLi) phases were precipitated within grains during heat treatment, while T1 phase also precipitated in the vicinity of grain boundaries. The evolution of inter- and intra-granular microstructures in AA1460 influenced the local and global electrochemical characteristics, which in turn influenced the temper dependent corrosion morphologies of AA1460. A correlation between OCP and corrosion mode was proposed, which may be used to compare the IGC sensitivity of AA1460 with different tempers.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Huang, Jia-lei and Li, Jin-feng and Liu, Dan-yang and Zhang, Rui-feng and Chen, Yong-lai and Zhang, Xu-hu and Ma, Peng-cheng and Gupta, Rajeev Kumar and Birbilis, Nick.}, year={2018}, month={Jul}, pages={215–226} }
 @article{esquivel_darling_murdoch_gupta_2018, title={Corrosion and Mechanical Properties of Al-5 At. Pct Cr Produced by Cryomilling and Subsequent Consolidation at Various Temperatures}, volume={49}, ISSN={1073-5623 1543-1940}, url={http://dx.doi.org/10.1007/s11661-018-4620-5}, DOI={10.1007/s11661-018-4620-5}, number={7}, journal={Metallurgical and Materials Transactions A}, publisher={Springer Science and Business Media LLC}, author={Esquivel, J. and Darling, K. A. and Murdoch, H. A. and Gupta, R. K.}, year={2018}, month={Apr}, pages={3058–3065} }
 @article{daroonparvar_yajid_kay_bakhsheshi-rad_gupta_yusof_ghandvar_arshad_zulkifli_2018, title={Effects of Al2O3 diffusion barrier layer (including Y-containing small oxide precipitates) and nanostructured YSZ top coat on the oxidation behavior of HVOF NiCoCrAlTaY/APS YSZ coatings at 1100 °C}, volume={144}, ISSN={0010-938X}, url={http://dx.doi.org/10.1016/j.corsci.2018.07.013}, DOI={10.1016/j.corsci.2018.07.013}, abstractNote={In this research, the effects of thin Al2O3 diffusion barrier layer (including Y-containing small oxide precipitates) and nanostructured YSZ top coat on the high temperature oxidation behavior of HVOF NiCoCrAlTaY/APS YSZ coatings were examined by using isothermal oxidation tests at 1100 °C. Nanostructured YSZ top coat could slightly reduce the double layered TGO growth rate and weight gain of thermal barrier coating systems. However, Al2O3 diffusion barrier layer (consisting of Y-containing small oxide precipitates) could substantially decline the oxidation rate and Ta movement (Ta-enriched oxides formation) in the NiCoCrAlTaY/Al2O3/nanostructured YSZ coating at 1100 °C.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Daroonparvar, Mohammadreza and Yajid, Muhamad Azizi Mat and Kay, Charls M. and Bakhsheshi-Rad, Hamidreza and Gupta, Rajeev Kumar and Yusof, Noordin Mohd and Ghandvar, Hamidreza and Arshad, Azrina and Zulkifli, Intan Syaqirah Mohd}, year={2018}, month={Nov}, pages={13–34} }
 @article{esquivel_murdoch_darling_gupta_2018, title={Excellent corrosion resistance and hardness in Al alloys by extended solid solubility and nanocrystalline structure}, volume={6}, url={https://doi.org/10.1080/21663831.2017.1396262}, DOI={10.1080/21663831.2017.1396262}, abstractNote={ABSTRACT Development of ultra-high strength and corrosion-resistant aluminum (Al) alloys is demonstrated by a combination of suitable alloying elements and processing technology able to cause extended solid solubility and nanocrystalline structure. Binary Al-transition metal (M: Cr, Ni, Mo, Si, Ti, Mn, V, Nb) alloys, produced by high-energy ball milling and subsequent cold compaction, have exhibited significantly high hardness and corrosion resistance compared to any commercial Al alloy. The cyclic potentiodynamic polarization tests revealed a significant improvement in pitting and repassivation potentials. X-ray diffraction analysis revealed the grain refinement <100 nm and extended solid solubility. GRAPHICAL ABSTRACT IMPACT STATEMENT High-energy ball-milled Al alloys, owing to excellent corrosion resistance and high hardness, are expected to be a new class of Al alloys and initiate a multidisciplinary research direction.}, number={1}, journal={Materials Research Letters}, publisher={Informa UK Limited}, author={Esquivel, J. and Murdoch, H. A. and Darling, K. A. and Gupta, R. K.}, year={2018}, month={Jan}, pages={79–83} }
 @article{khan_mirza_gupta_2018, title={High hardness and thermal stability of nanocrystalline Mg–Al alloys synthesized by the high-energy ball milling}, volume={4}, url={https://doi.org/10.1016/j.mtla.2018.10.004}, DOI={10.1016/j.mtla.2018.10.004}, abstractNote={In present study, nanocrystalline Mg-xAl (x= 0, 5, 10 and 20 wt%) alloys were produced via high-energy ball milling (HEBM) followed by compaction under uniaxial pressure of 3 GPa at room temperature. The produced alloys were subjected to heat treatment (HT) for 1 h at various temperatures ranging from room temperature to 425 °C. The microstructure of the milled and subsequently heat treated alloys was studied using scanning electron microscope (SEM) and X-ray diffraction analysis (XRD). Lattice parameters changed upon addition of Al and in HT temperature, which have been discussed qualitatively based on electron to atom ratio curve. Hardness measurements, performed at room temperature using Vicker's microindenter, revealed that hardness of the ball milled Mg-xAl alloys was higher than many commercial Mg alloys. Hardness of the alloys was influenced by the Al addition and HT, and it was correlated with the crystallite size and microstructure. High hardness of Mg-xAl alloys was attributed to the grain refinement and Al addition.}, journal={Materialia}, publisher={Elsevier BV}, author={Khan, M.U.F. and Mirza, F. and Gupta, R.K.}, year={2018}, month={Dec}, pages={406–416} }
 @article{esquivel_gupta_2018, title={Influence of the V content on microstructure and hardness of high-energy ball milled nanocrystalline Al-V alloys}, volume={760}, url={https://doi.org/10.1016/j.jallcom.2018.05.132}, DOI={10.1016/j.jallcom.2018.05.132}, abstractNote={Nanocrystalline Al-xV (x = 0, 0.5, 2, 5, 10 and 20 at. %) alloys were produced by high-energy ball milling (HEBM) followed by consolidation at room temperature under uniaxial pressure of 3 GPa. Grain size, dispersion of the alloying element (V) and formation of solid solution were studied using X-ray diffraction (XRD) analysis and scanning electron microscope (SEM) coupled with energy dispersive X-ray spectroscopy (EDXS). High-energy ball milling imparted nanocrystalline structure and high solid solubility of V in Al - several orders of magnitude higher than the thermodynamically predicted value. Hardness of Al-xV alloys, which increased with increasing the V content, was higher than the commercial Al alloys. High hardness of the Al-xV alloys was attributed to the solid solution strengthening caused by high solid solubility of V and grain refinement <100 nm.}, journal={Journal of Alloys and Compounds}, publisher={Elsevier BV}, author={Esquivel, J. and Gupta, R.K.}, year={2018}, month={Sep}, pages={63–70} }
 @article{daroonparvar_yajid_gupta_yusof_bakhsheshi-rad_ghandvar_2018, title={Investigation of Corrosion Protection Performance of Multiphase PEO (Mg2SiO4, MgO, MgAl2O4) Coatings on Mg Alloy Formed in Aluminate-Silicate- based Mixture Electrolyte}, volume={54}, ISSN={2070-2051 2070-206X}, url={http://dx.doi.org/10.1134/s2070205118030231}, DOI={10.1134/s2070205118030231}, number={3}, journal={Protection of Metals and Physical Chemistry of Surfaces}, publisher={Pleiades Publishing Ltd}, author={Daroonparvar, Mohammadreza and Yajid, Muhamad Azizi Mat and Gupta, Rajeev Kumar and Yusof, Noordin Mohd and Bakhsheshi-Rad, Hamid Reza and Ghandvar, Hamidreza}, year={2018}, month={May}, pages={425–441} }
 @article{esquivel_wachowiak_o'brien_gupta_2018, title={Thermal stability of nanocrystalline Al-5at.%Ni and Al-5at.%V alloys produced by high-energy ball milling}, volume={744}, url={https://doi.org/10.1016/j.jallcom.2018.02.144}, DOI={10.1016/j.jallcom.2018.02.144}, abstractNote={Nanocrystalline Al-5at.%V and Al-5at.%Ni alloys, prepared by high-energy ball milling and subsequent consolidation under uniaxial pressure of 3 GPa, were subjected to isothermal heat treatment for one hour at various temperatures—ranging from 100 to 614 °C. Grain growth, solid solubility of the alloying elements, and formation of additional phases following heat treatment were investigated using X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDXS). Vickers hardness was measured after heat treatment and correlated with the heat treatment temperature, composition, and microstructure. The heat treatment temperature and alloying element had a strong influence on hardness. The Influence of heat treatment on the microstructure and hardness of the alloys was dependent upon the diffusion coefficients of the alloying elements in Al.}, journal={Journal of Alloys and Compounds}, publisher={Elsevier BV}, author={Esquivel, J. and Wachowiak, M.G. and O'Brien, S.P. and Gupta, R.K.}, year={2018}, month={May}, pages={651–657} }
 @article{gupta_esquivel_2017, title={(Invited) High Strength and Corrosion Resistant Light Alloys Via High-Energy Ball Milling}, url={https://doi.org/10.1149/MA2017-02/10/720}, DOI={10.1149/MA2017-02/10/720}, abstractNote={ 	The corrosion of metallic materials in a given environment depends on the microstructure stemmed from the concurrent influence of the composition, production route, thermomechanical processing, and service conditions. Microstructures and therefore the properties of the alloys produced via high-energy ball milling are known to be significantly different than that produced via conventional techniques even for the same alloy composition. Grain refinement, extended solid solubilities, formation of metastable phases, unique grain boundaries, super saturation of vacancies, high stored energy, increased diffusivities are some of the principle characteristics of the microstructure produced by the high-energy ball milling process. }, journal={ECS Meeting Abstracts}, publisher={The Electrochemical Society}, author={Gupta, Rajeev Kumar and Esquivel, Javier}, year={2017}, month={Sep} }
 @article{gupta_mirza_khan_esquivel_2017, title={Aluminum containing Na2CrO4: Inhibitor release on demand}, volume={205}, ISSN={0167-577X}, url={http://dx.doi.org/10.1016/j.matlet.2017.06.080}, DOI={10.1016/j.matlet.2017.06.080}, abstractNote={The paper presents a new concept of metallic materials containing inhibitor, able to inhibit corrosion as it initiates. Al particles with uniformly dispersed sodium chromate (0.5–20 wt%) were produced by high-energy ball milling followed by cold compaction. Cyclic potentiodynamic polarization tests and surface analysis after constant immersion tests revealed a significant improvement in corrosion behavior due to the sodium chromate addition up to 5 wt%. Improved corrosion behavior was attributed to the release of inhibitor as corrosion occurred. X-ray photoelectron spectroscopy indicated presence of the Cr3+ in the passive film.}, journal={Materials Letters}, publisher={Elsevier BV}, author={Gupta, R.K. and Mirza, F. and Khan, M.U.F. and Esquivel, J.}, year={2017}, month={Oct}, pages={194–197} }
 @book{gupta_murty_birbilis_2017, title={An Overview of High-energy Ball Milled Nanocrystalline Aluminum Alloys}, ISBN={9783319570297 9783319570310}, ISSN={2192-1091 2192-1105}, url={http://dx.doi.org/10.1007/978-3-319-57031-0}, DOI={10.1007/978-3-319-57031-0}, abstractNote={This book presents a comprehensive overview of the nanocrystalline Al based alloys as prepared using high-energy ball milling (HEBM). It discusses the influence of HEBM parameters on grain refinement}, journal={SpringerBriefs in Materials}, publisher={Springer International Publishing}, author={Gupta, Rajeev Kumar and Murty, B. S. and Birbilis, Nick}, year={2017} }
 @article{esquivel_gupta_2017, title={Corrosion Behavior and Hardness of Al–M (M: Mo, Si, Ti, Cr) Alloys}, volume={30}, ISSN={1006-7191 2194-1289}, url={http://dx.doi.org/10.1007/s40195-017-0550-2}, DOI={10.1007/s40195-017-0550-2}, abstractNote={The corrosion behavior of Al–5 at.% Cr, Al–5 at.% Si, Al–5 at.% Mo and Al–5 at.% Ti produced via casting and Al–5 at.% Cr produced by high-energy ball milling and subsequent consolidation by cold pressing was studied using potentiodynamic polarization and surface analysis following constant immersion tests. Alloys were characterized using a scanning electron microscope coupled with the energy-dispersive X-ray spectroscopy and X-ray diffraction analysis. Hardness, a representative of the strength, was also measured. The alloys produced by casting contained coarse intermetallics and therefore exhibited poor corrosion resistance. Al–5 at.% Cr alloy produced by high-energy ball milling exhibited a significantly improved corrosion resistance and hardness, which was attributed to the grain refinement to nanoscale and extended solid solubility of Cr in Al. The study indicated that the high-energy ball milling was capable of producing Al alloys with improved corrosion behavior and hardness.}, number={4}, journal={Acta Metallurgica Sinica (English Letters)}, publisher={Springer Science and Business Media LLC}, author={Esquivel, J. and Gupta, R. K.}, year={2017}, month={Feb}, pages={333–341} }
 @article{tan_varela_huo_gupta_abreu_mahdavi_hinton_forsyth_2016, title={An Overview of New Progresses in Understanding Pipeline Corrosion}, volume={15}, url={https://doi.org/10.14773/CST.2016.15.6.271}, DOI={10.14773/cst.2016.15.6.271}, abstractNote={An approach to achieving the ambitious goal of cost effectively extending the safe operation life of energy pipeline to 100 years is the application of health monitoring and life prediction tools that are able to provide both long-term remnant pipeline life prediction and in-situ pipeline condition monitoring. A critical step is the enhancement of technological capabilities that are required for understanding and quantifying the effects of key factors influencing buried steel pipeline corrosion and environmentally assisted materials degradation, and the development of condition monitoring technologies that are able to provide in-situ monitoring and site-specific warning of pipeline damage. This paper provides an overview of our current research aimed at developing new sensors and electrochemical cells for monitoring, categorising and quantifying the level and nature of external pipeline and coating damages under the combined effects of various inter-related variables and processes such as localised corrosion, coating cracking and disbondment, cathodic shielding, transit loss of cathodic protection.}, number={6}, journal={Corrosion Science and Technology}, publisher={한국부식방식학회}, author={Tan, M. YJ and Varela, F. and Huo, Y. and Gupta, R. and Abreu, D. and Mahdavi, F. and Hinton, B. and Forsyth, M.}, year={2016}, month={Dec}, pages={271–280} }
 @article{gupta_tan_esquivel_forsyth_2016, title={Occurrence of Anodic Current and Corrosion of Steel in Aqueous Media Under Fluctuating Cathodic Protection Potentials}, volume={72}, ISSN={0010-9312 1938-159X}, url={http://dx.doi.org/10.5006/1637}, DOI={10.5006/1637}, abstractNote={Excursion of cathodic protection (CP) potential from the designed “safe” CP level resulting from various forms of electrical interference signals are observed rather frequently in industrial applications, in particular in the pipeline industry; however, the influence of such potential fluctuations on the corrosion behavior of steel under CP conditions does not yet appear to be fully understood. In this work, the effects of anodic transients that periodically shift the potential of a CP protected steel electrode from −1,200 mVAg/AgCl to −750 mVAg/AgCl on the corrosion of a steel electrode in aqueous media was investigated using square wave polarization. Anodic currents were measured that lasted for significant periods of time upon stepping the CP potential up to a less cathodic potential at various frequencies (1 h, 30 s, 10 s, 5 s, and 1 s). Part of such anodic currents is found to cause steel corrosion, and this is explained on the basis of understanding the Fe/H2O equilibrium.}, number={10}, journal={CORROSION}, publisher={NACE International}, author={Gupta, R.K. and Tan, M.Y.J. and Esquivel, J. and Forsyth, M.}, year={2016}, month={Oct}, pages={1243–1251} }
 @article{zhang_gupta_davies_hodge_tort_xia_birbilis_2016, title={The Influence of Grain Size and Grain Orientation on Sensitization in AA5083}, volume={72}, DOI={10.5006/1703}, abstractNote={Aluminum alloy AA5083 specimens (with a nominal composition of Al-4.4Mg-0.5Mn) from the same original plate were prepared with a variation in grain size imparted by cold rolling, cryo-rolling, equal channel angular pressing and high-pressure torsion. Electron backscatter diffraction was used to determine the grain size and misorientation. The effect of grain size on the degree of sensitization for AA5083 was studied via the ASTM G67 nitric acid mass lost test, upon specimens artificially sensitized at 150°C for 7 d. It was revealed that the intergranular corrosion caused by sensitization in AA5083 was significantly influenced by the grain size and processing methods used for grain refinement.}, number={2}, journal={Corrosion}, author={Zhang, R. and Gupta, R.K. and Davies, C.H.J. and Hodge, A.M. and Tort, M. and Xia, K. and Birbilis, N.}, year={2016}, pages={160–168} }
 @article{gupta_li_xia_zhou_sha_gun_ringer_birbilis_2015, title={Corrosion Behaviour of Al-4Mg-1Cu (wt%) Microalloyed with Si and Ag}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84930609120&partnerID=MN8TOARS}, DOI={10.1002/adem.201500163}, abstractNote={The microstructure, hardness, and corrosion behavior of Al–4Mg–1Cu–0.5Si and Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) following various aging times is investigated. Potentiodynamic polarisation and immersion tests reveal an apparent insensitivity in corrosion rates for the alloys studied with aging, along with a higher pitting corrosion resistance for the Ag containing alloy. The addition of Ag to the base Al–4Mg–1Cu–0.5Si composition increases the age hardening response and corrosion performance by modifying the morphology, size, and chemical composition of precipitates (from S‐phase to Z‐phase).}, journal={Advanced Engineering Materials}, author={Gupta, R.K. and Li, C. and Xia, J. and Zhou, X. and Sha, G. and Gun, B. and Ringer, S.P. and Birbilis, N.}, year={2015} }
 @article{gupta_fabijanic_zhang_birbilis_2015, title={Corrosion behaviour and hardness of in situ consolidated nanostructured Al and Al-Cr alloys produced via high-energy ball milling}, volume={98}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84937977468&partnerID=MN8TOARS}, DOI={10.1016/j.corsci.2015.06.011}, abstractNote={This paper presents a hypothesis and its experimental validation that simultaneous improvement in the hardness and corrosion resistance of aluminium can be achieved by the combination of suitable processing route and alloying additions. More specifically, the corrosion resistance and hardness of Al–xCr (x = 0–10 wt.%) alloys as produced via high-energy ball milling were significantly higher than pure Al and AA7075-T651. The improved properties of the Al–xCr alloys were attributed to the Cr addition and high-energy ball milling, which caused nanocrystalline structure, extended solubility of Cr in Al, and uniformly distributed fine intermetallic phases in the Al–Cr matrix.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Gupta, R.K. and Fabijanic, D. and Zhang, R. and Birbilis, N.}, year={2015}, pages={643–650} }
 @article{dorin_stanford_birbilis_gupta_2015, title={Influence of cooling rate on the microstructure and corrosion behavior of Al–Fe alloys}, volume={100}, DOI={10.1016/j.corsci.2015.08.017}, abstractNote={The effect of Fe in Al is technologically important for commercial Al-alloys, and in recycled Al. This work explores the use of the novel rapid solidification technology, known as direct strip casting, to improve the recyclability of Al-alloys. We provide a comparison between the corrosion and microstructure of Al–Fe alloys prepared with wide-ranging cooling rates (0.1 °C/s to 500 °C/s). Rapid cooling was achieved via direct strip casting, while slow cooling was achieved using sand casting. Corrosion was studied via polarisation and immersion tests, followed by surface analysis using scanning electron microscopy and optical profilometry. It was shown that the corrosion resistance of Al–Fe alloys is improved with increased cooling rates, attributed to the reduced size and number of Fe-containing intermetallics.}, journal={Corrosion Science}, publisher={Elsevier BV}, author={Dorin, T. and Stanford, N. and Birbilis, N. and Gupta, R.K.}, year={2015}, month={Nov}, pages={396–403} }
 @article{gupta_fabijanic_dorin_qiu_wang_birbilis_2015, title={Simultaneous improvement in the strength and corrosion resistance of Al via high-energy ball milling and Cr alloying}, volume={84}, ISSN={0264-1275}, url={http://dx.doi.org/10.1016/j.matdes.2015.06.120}, DOI={10.1016/j.matdes.2015.06.120}, abstractNote={The corrosion resistance and mechanical properties of nanocrystalline aluminium (Al) and Al–20 wt.%Cr alloys, synthesized by high-energy ball milling followed by spark plasma sintering, were investigated. Both alloys exhibited an excellent combination of corrosion resistance and compressive yield strength, which was attributed to the nanocrystalline structure, extended solubility, uniformly distributed fine particles, and homogenous microstructure induced by high-energy ball milling. This work demonstrates the possibilities of developing ultra-high strength Al alloys with excellent corrosion resistance, exploiting conventionally insoluble elements or alloying additions via suitable processing routes.}, journal={Materials & Design}, publisher={Elsevier BV}, author={Gupta, R.K. and Fabijanic, D. and Dorin, T. and Qiu, Y. and Wang, J.T. and Birbilis, N.}, year={2015}, month={Nov}, pages={270–276} }
 @article{gupta_birbilis_2015, title={The influence of nanocrystalline structure and processing route on corrosion of stainless steel: A review}, volume={92}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84921433088&partnerID=MN8TOARS}, DOI={10.1016/j.corsci.2014.11.041}, abstractNote={Nanocrystalline materials with a grain size <100 nm have attracted significant attention over the past two decades. Various attempts have been made to prepare nanocrystalline stainless steel using various routes, along with the study of attendant corrosion properties. A nanocrystalline structure imparts an improvement in mechanical properties, coupled with distinct corrosion behaviour, not always leading to better corrosion resistance. This paper reviews the relevant works to date which have studied corrosion behaviour of nanocrystalline stainless steels, relating the performance to processing, along with attention given to mechanistic aspects which dictate corrosion of nanocrystalline stainless steel.}, journal={Corrosion Science}, author={Gupta, R.K. and Birbilis, N.}, year={2015}, pages={1–15} }
 @article{frankel_chen_gupta_kandasamy_birbilis_2014, title={Effect of Vacuum System Base Pressure on Corrosion Resistance of Sputtered Al Thin Films}, volume={161}, ISSN={0013-4651 1945-7111}, url={http://dx.doi.org/10.1149/2.056404jes}, DOI={10.1149/2.056404jes}, abstractNote={Pure aluminum (Al) thin films were sputter deposited under conditions of variable base pressure of the deposition tool. The purpose of the study was to identify if the base pressure had a key influence on the electrochemical properties, namely corrosion resistance, of the Al deposits. The corrosion resistance was found to increase with increasingly high base pressure (i.e. lower quality vacuum). Potentiodynamic polarization experiments, pit growth studies, TEM and XPS were employed. From the results is posited that improved corrosion resistance is due to the presence of oxygen (O) being incorporated into the films during deposition resulting an O-containing (i.e. Al-O) alloy. This effect is important to identify because of the many reports in the literature of high pitting potentials for Al thin films, from studies with widely varying base pressure. Vacuum system base pressure was found to have a large effect on the corrosion resistance. A maximum base pressure in the low 10-7 Torr range is recommended to minimize oxygen uptake into the film.}, number={4}, journal={Journal of The Electrochemical Society}, publisher={The Electrochemical Society}, author={Frankel, G. S. and Chen, X.-B. and Gupta, R. K. and Kandasamy, S. and Birbilis, N.}, year={2014}, pages={C195–C200} }
 @article{sukiman_gupta_buchheit_birbilis_2014, title={Influence of microalloying additions on Al-Mg alloy. Part 1: Corrosion and electrochemical response}, volume={49}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84901407887&partnerID=MN8TOARS}, DOI={10.1179/1743278213Y.0000000128}, abstractNote={A range of custom alloys based on the Al–4Mg–0·4Mn system were produced with selected quaternary microalloying additions. Alloying elements studied include silicon, zinc, lead, titanium, tin, zirconium, strontium and neodymium. To characterise the corrosion response, electrochemical tests were carried out in 0·1M NaCl, supplemented by constant immersion tests and basic microstructural characterisation by means of scanning electron microscopy (SEM). Optical profilometery was used to determine the form and intensity of localised corrosion. The results indicate that low level quaternary alloying additions can have a marked influence on specific aspects of the first order correlation between chemistry, microstructure, hardness and corrosion.}, number={4}, journal={Corrosion Engineering Science and Technology}, author={Sukiman, N.L. and Gupta, R.K. and Buchheit, R.G. and Birbilis, N.}, year={2014}, pages={254–262} }
 @article{sukiman_gupta_zhang_buchheit_birbilis_2014, title={Influence of microalloying additions on Al-Mg alloy. Part 2: Phase analysis and sensitization behaviour}, volume={49}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84901446388&partnerID=MN8TOARS}, DOI={10.1179/1743278213Y.0000000129}, abstractNote={A range of alloys based on the Al-4Mg-0·4Mn system were produced with selected quaternary microalloying additions. In Part 1 of this study, the electrochemical and corrosion response was studied. To characterise the sensitisation behaviour of these alloys, where sensitisation is the major mode of degradation of 5xxx alloys, heat treatment at 150°C was carried out and followed by the Nitric Acid Mass Loss Test (NAMLT) according to ASTM G67-04. Herein the alloying elements studied include silicon, zinc, titanium, zirconium and strontium. The results indicate that strontium (Sr), silicon (Si) and titanium (Ti) have a significant influence in reducing intergranular corrosion (IGC) susceptibility.}, number={4}, journal={Corrosion Engineering Science and Technology}, author={Sukiman, N.L. and Gupta, R.K. and Zhang, R. and Buchheit, R.G. and Birbilis, N.}, year={2014}, pages={263–268} }
 @inproceedings{mahdavi_tan_forsyth_gupta_abreu_2014, title={Studying the cathodic disbondment of coatings using electrochemical impedance spectroscopy}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84919343962&partnerID=MN8TOARS}, booktitle={Annual Conference of the Australasian Corrosion Association 2014: Corrosion and Prevention 2014}, author={Mahdavi, F. and Tan, M.Y.J. and Forsyth, M. and Gupta, R. and Abreu, D.}, year={2014} }
 @article{gupta_hinton_birbilis_2014, title={The effect of chromate on the pitting susceptibility of AA7075-T651 studied using potentiostatic transients}, volume={82}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84894782622&partnerID=MN8TOARS}, DOI={10.1016/j.corsci.2014.01.012}, abstractNote={The effect of chromate on metastable pitting of AA7075-T651 as determined via potentiostatic polarisation is reported. A systematic study of metastable pitting and its correlation with stable pits was conducted in various concentrations of sodium chromate (Na2CrO4), revealing the metastable pitting rate was able to provide a quantitative metric for pitting corrosion. The size and number of metastable pits decreased significantly in the presence of chromate. The present study is intended as a general baseline for the assessment of future chromate replacement technologies, as elaborated herein.}, journal={Corrosion Science}, author={Gupta, R.K. and Hinton, B.R.W. and Birbilis, N.}, year={2014}, pages={197–207} }
 @article{gupta_zhang_davies_birbilis_2014, title={Theoretical study of the influence of microalloying on sensitization of AA5083 and moderation of sensitization of a model Al-Mg-Mn alloy via Sr additions}, volume={70}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84898931322&partnerID=MN8TOARS}, DOI={10.5006/1117}, abstractNote={The calculated effect of a range of quaternary alloying additions to aluminum alloy (AA)5083 (Al-4.4Mg-0.5Mn [UNS A95083]) was investigated. Attention was given to the influence of composition on the volume fraction of β-phase (Mg2Al3), and the possible formation of any additional phases (which we term γ-phase herein). Alloying additions of silver, cerium, copper, lithium, neodymium, nickel, scandium, silicon, strontium, yttrium, zinc, and zirconium were studied in hypothetical additions of 0.1 wt% and 0.5 wt%, revealing that there is potential to modify the fraction of β-phase, and hence sensitization, in AA5083. Calculations indicated strontium to be the most effective addition in decreasing β-phase fraction during thermal exposure (sensitization); therefore, the influence of Sr additions were studied empirically via production of custom Al-Mg-Mn alloys. Sensitization was investigated via the nitric acid mass loss test (NAMLT), revealing that mass loss from intergranular corrosion decreased by more than...}, number={4}, journal={Corrosion}, author={Gupta, R.K. and Zhang, R. and Davies, C.H.J. and Birbilis, N.}, year={2014}, pages={402–413} }
 @inproceedings{gupta_tan_forsyth_hinton_2013, title={An overview of methods for simulating and evaluating pipeline corrosion}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84914674678&partnerID=MN8TOARS}, booktitle={Annual Conference of the Australasian Corrosion Association 2013: Corrosion and Prevention 2013}, author={Gupta, R.K. and Tan, M.Y. and Forsyth, M. and Hinton, B.R.W.}, year={2013}, pages={513–521} }
 @article{gupta_raman_koch_murty_2013, title={Effect of nanocrystalline structure on the corrosion of a Fe20Cr alloy}, volume={8}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84878702475&partnerID=MN8TOARS}, number={5}, journal={International Journal of Electrochemical Science}, author={Gupta, R.K. and Raman, R.K.S. and Koch, C.C. and Murty, B.S.}, year={2013}, pages={6791–6806} }
 @article{zhou_ralston_laws_cao_gupta_ferry_birbilis_2013, title={Effect of the degree of crystallinity on the electrochemical behavior of Mg65Cu25Y10 and Mg70Zn 25Ca5 bulk metallic glasses}, volume={69}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84881174030&partnerID=MN8TOARS}, DOI={10.5006/0870}, abstractNote={The effect of varying the percent crystallinity on the electrochemical behavior of Mg65Cu25Y10 and Mg70Zn25Ca5 bulk metallic glasses was studied. The alloys were heat-treated to achieve desired microstructures ranging from fully amorphous to fully crystalline, providing a systematic basis for subsequent testing. Potentiodynamic experiments in 0.01 M sodium chloride (NaCl) were used, whereby both the amorphous and partially crystallized samples were observed to have more noble corrosion potentials and lower anodic kinetics. However, this was accompanied by more rapid cathodic kinetics relative to their fully crystalline counterparts, meaning that corrosion rates were not significantly lower in the amorphous state. To describe the electrochemical response as a function of the degree of crystallinity, differential scanning calorimetry (DSC), scanning electron microscopy, x-ray diffraction (XRD), and electrical conductivity measurements were undertaken, where it was found that crystallinity alone is not necessarily the controlling factor and microchemistry that evolves upon devitrification, plays a key role in the electrochemical response of these materials.}, number={8}, journal={Corrosion}, author={Zhou, X. and Ralston, K.D. and Laws, K.J. and Cao, J.D. and Gupta, R.K. and Ferry, M. and Birbilis, N.}, year={2013}, pages={781–792} }
 @article{sukiman_shi_gupta_buchheit_birbilis_2013, title={Electrochemical and corrosion response of commercially pure aluminum alloyed with binary additions of strontium}, volume={160}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84877105941&partnerID=MN8TOARS}, DOI={10.1149/2.001308jes}, abstractNote={The influence of strontium (Sr) on the electrochemical response and corrosion of aluminum (Al) was studied over the range of 0 to 2.45 wt.% binary Sr additions. There is a paucity of prior information regarding the influence of Sr upon Al in any context, and the results herein revealed that corrosion attack is not predominantly associated with Sr containing phases, but rather Fe-rich constituents. Al4Sr intermetallic particles appear to be electrochemically homogeneous with the Al-matrix, which is both unique and important in the context of Al-alloy corrosion. The changes in corrosion rate with increasing Sr content are generally subtle, with a relative increase observed at approximately ∼0.1 wt.% Sr, followed by a reduction in corrosion rate with increasing Sr.}, number={8}, journal={Journal of the Electrochemical Society}, author={Sukiman, N.L. and Shi, H. and Gupta, R.K. and Buchheit, R.G. and Birbilis, N.}, year={2013} }
 @article{lyndon_gupta_gibson_birbilis_2013, title={Electrochemical behaviour of the β-phase intermetallic (Mg2Al3) as a function of pH as relevant to corrosion of aluminium-magnesium alloys}, volume={70}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84875245571&partnerID=MN8TOARS}, DOI={10.1016/j.corsci.2012.12.022}, abstractNote={The intermetallic phase Mg2Al3 was synthesised in bulk form to permit electrochemical characterisation. Polarisation testing was performed in 0.01 M NaCl across the pH range of 2–10, which is relevant to instances where the Mg2Al3 phase populates Al-alloys (i.e. 5xxx series). Mg2Al3 is capable of sustaining high dissolution rates, but this is pH dependent. As such, the range of currents sustained over the E-pH space are reported and are of general use for reconciling localised corrosion or corrosion model feedstock in other works.}, journal={Corrosion Science}, author={Lyndon, J.A. and Gupta, R.K. and Gibson, M.A. and Birbilis, N.}, year={2013}, pages={290–293} }
 @article{gupta_wang_zhang_sukiman_davies_birbilis_2013, title={Imparting sensitization resistance to an Al-5Mg alloy via neodymium additions}, volume={69}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84872336912&partnerID=MN8TOARS}, DOI={10.5006/0833}, abstractNote={Low-level Nd additions, up to 0.17 wt%, were added to Al-5Mg to explore the impact on the subsequent degree of sensitization. Following heat treatment at 150°C for 1 day and 7 days, nitric acid mass loss (NAMLT) tests revealed that additions of >0.11% Nd were effective at decreasing the amount of subsequent intergranular attack.}, number={1}, journal={Corrosion}, author={Gupta, R.K. and Wang, Y. and Zhang, R. and Sukiman, N.L. and Davies, C.H.J. and Birbilis, N.}, year={2013}, pages={4–8} }
 @article{gupta_zhang_davies_birbilis_2013, title={Influence of Mg content on the sensitization and corrosion of Al-xMg(-Mn) alloys}, volume={69}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84888626825&partnerID=MN8TOARS}, DOI={10.5006/0948}, abstractNote={The influence of Mg content on the degree of sensitization (DoS) of Al-xMg-0.5Mn (wt%) alloys (where x varies from 3.36 wt% to 8.85 wt%) was investigated via the nitric acid mass loss test (NAMLT). NAMLT upon sensitized specimens revealed that mass loss was negligible below ~4.01 wt% Mg, while for Mg content ≥4.01 wt%, mass loss increased monotonically. The calculated equilibrium β-phase fractions were contrast with the DoS values. Additionally, the influence of the Mg content on corrosion was investigated via potentiodynamic polarization testing, in conjunction with microhardness measurements. We found that Mg additions lead to an increase in hardness without causing any significant impact on electrochemically determined corrosion current density; however, Mg content has a major impact on intergranular corrosion as determined from NAMLT.}, number={11}, journal={Corrosion}, author={Gupta, R.K. and Zhang, R. and Davies, C.H.J. and Birbilis, N.}, year={2013}, pages={1081–1087} }
 @article{wang_gupta_sukiman_zhang_davies_birbilis_2013, title={Influence of alloyed Nd content on the corrosion of an Al-5Mg alloy}, volume={73}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84878359780&partnerID=MN8TOARS}, DOI={10.1016/j.corsci.2013.03.034}, abstractNote={The influence of neodymium (Nd) additions from 0 to 0.17 wt.% on the electrochemical response, corrosion, and hardness of a model 5xxx alloy (Al–5Mg) was studied. The combination of SEM, polarisation, constant immersion and nitric acid mass loss testing, followed by optical profilometry, revealed that Nd had no significant effect on pitting or general corrosion of Al–5Mg; however with Nd additions the extent of intergranular corrosion following sensitisation was decreased substantially. Nd additions also increased alloy hardness and thus microalloying with Nd was shown to improve the properties of Al–5Mg.}, journal={Corrosion Science}, author={Wang, Y. and Gupta, R.K. and Sukiman, N.L. and Zhang, R. and Davies, C.H.J. and Birbilis, N.}, year={2013}, pages={181–187} }
 @article{birbilis_zhang_lim_gupta_davies_lynch_kelly_scully_2013, title={Quantification of sensitization in AA5083-H131 via imaging ga-embrittled fracture surfaces}, volume={69}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84876941910&partnerID=MN8TOARS}, DOI={10.5006/0804}, abstractNote={Sensitization of 5xxx series Al alloys involving precipitation of β phase (Mg2Al3) at grain boundaries was studied for different exposure times at 100°C upon AA5083-H131 (UNS A95083). In this work, we reveal that fracture surfaces prepared by liquid gallium embrittlement can yield a quantification of grain boundary β phase with significant statistics on β phase size and spacing. This information is a necessary first step toward development of quantitative damage models to describe inter-granular corrosion (IGC) and stress corrosion (IGSCC).}, number={4}, journal={Corrosion}, author={Birbilis, N. and Zhang, R. and Lim, M.L.C. and Gupta, R.K. and Davies, C.H.J. and Lynch, S.P. and Kelly, R.G. and Scully, J.R.}, year={2013}, pages={396–402} }
 @inproceedings{gupta_deschamps_birbilis_2012, title={Characterisation of the evolution of microstructure and electrochemical properties for 7xxx aluminium alloys}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84876883337&partnerID=MN8TOARS}, booktitle={Annual Conference of the Australasian Corrosion Association 2012}, author={Gupta, R.K. and Deschamps, A. and Birbilis, N.}, year={2012}, pages={646–651} }
 @article{gupta_sukiman_fleming_gibson_birbilis_2012, title={Electrochemical behavior and localized corrosion associated with Mg2Si particles in Al and Mg alloys}, volume={1}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84880429848&partnerID=MN8TOARS}, DOI={10.1149/2.002201eel}, abstractNote={The electrochemical characteristics of Mg2Si in dilute NaCl over a range of pH values are presented. In this study, Mg2Si was carefully synthesized to permit the collection of its anodic and cathodic potentiodynamic polarization response. Difficulties in producing bulk Mg2Si means that such data remains scarce to date. Mg2Si is an important intermetallic that forms in Al and Mg alloys containing silicon. In this work, the electrochemical response of Mg2Si is interpreted (and contrasted) in the context of Al and Mg alloys that contain Mg2Si, revealing that Mg2Si is either a local anode or local cathode.}, number={1}, journal={ECS Electrochemistry Letters}, author={Gupta, R.K. and Sukiman, N.L. and Fleming, K.M. and Gibson, M.A. and Birbilis, N.}, year={2012} }
 @article{gupta_raman_koch_2012, title={Electrochemical characteristics of nano and microcrystalline Fe-Cr alloys}, volume={47}, ISSN={["1573-4803"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84864455905&partnerID=MN8TOARS}, DOI={10.1007/s10853-012-6529-5}, number={16}, journal={JOURNAL OF MATERIALS SCIENCE}, author={Gupta, Rajeev K. and Raman, R. K. Singh and Koch, C. C.}, year={2012}, month={Aug}, pages={6118–6124} }
 @inproceedings{sukiman_gupta_birbilis_buchheit_2012, title={General aspects of the corrosion of aluminium alloys}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84876835236&partnerID=MN8TOARS}, booktitle={Annual Conference of the Australasian Corrosion Association 2012}, author={Sukiman, N.L. and Gupta, R.K. and Birbilis, N. and Buchheit, R.G.}, year={2012}, pages={696–702} }
 @article{gupta_sukiman_cavanaugh_hinton_hutchinson_birbilis_2012, title={Metastable pitting characteristics of aluminium alloys measured using current transients during potentiostatic polarisation}, volume={66}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84857994556&partnerID=MN8TOARS}, DOI={10.1016/j.electacta.2012.01.090}, abstractNote={In this study we report a comparison between the metastable pitting observed upon AA2024-T3, AA5005-H34, AA5083-H116, AA6022-O, AA7075-T651 and pure Al, over a range of potentials. Metastable pitting increased with microstructural (hence electrochemical) heterogeneity of the alloys studied, which roughly correlates with hardness. In alloys exhibiting a low pitting propensity, metastable pitting activity completely ceased as the underpotential from Epit was increased, whereas for corrosion prone alloys, metastable activity continued independently of underpotential. The selection of the test potential is also a key factor in using the method described herein. It is shown that the Epit value bears little correlation with the number of pits formed during long-term exposure as measured using optical profilometry, whereas the metastable pitting rate bears a correlation to the actual pit density.}, journal={Electrochimica Acta}, author={Gupta, R.K. and Sukiman, N.L. and Cavanaugh, M.K. and Hinton, B.R.W. and Hutchinson, C.R. and Birbilis, N.}, year={2012}, pages={245–254} }
 @inbook{birbilis_zhang_gupt_2012, title={Oxidation Resistance of Nanocrystalline Alloys}, url={http://dx.doi.org/10.5772/34928}, DOI={10.5772/34928}, abstractNote={Nanocrystalline (nc) materials are single or multi-phase polycrystalline solids with a grain size of a few nanometers, typically less than 100 nm. Owing to the very fine grain size, the volume fraction of atoms located at grain boundaries or interfaces increases significantly in nanocrystalline materials [1]. A simple geometrical estimation, where the grains are assumed as spheres or cubes, yields the following values for the volume fraction of the interfaces: 50% for 5 nm grains, 30% for 10 nm grains and about 3% for 100 nm grains [2-5]. These values of interface volume fraction are several orders of magnitude higher than those of conventional microcrystalline materials. Consequently, nanocrystalline materials exhibit properties that are significantly different from and often improved over, their conventional microcrystalline (mc) counterparts. For example, nanocrystalline materials exhibit increased mechanical strength [6-10], enhanced diffusivity [11], improved corrosion resistance (some nanocrystalline materials) [12-20], optical, electrical and magnetic properties [21-24]. Due to their unique properties, nanocrystalline materials have attracted considerable research interests and the field of nanocrystalline materials has now become one of major identifiable activities in materials science and engineering.}, booktitle={Corrosion Resistance}, publisher={InTech}, author={Birbilis, Nick and Zhang, Jianqiang and Gupt, Rajeev}, editor={Shih, H.Editor}, year={2012}, month={Mar} }
 @article{gupta_deschamps_cavanaugh_lynch_birbilis_2012, title={Relating the early evolution of microstructure with the electrochemical response and mechanical performance of a Cu-rich and Cu-lean 7xxx aluminum alloy}, volume={159}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84875616681&partnerID=MN8TOARS}, DOI={10.1149/2.062211jes}, abstractNote={In this work AA7150 and AA7079 were studied as examples of 7xxx aluminum alloys with a high and low Cu content. The alloys were carefully examined to determine the evolution (incl. density and size) of precipitates during heat-treatment using small angle X-ray scattering (SAXS). Such characterization made it possible to relate the evolution of microstructure to specific properties such as electrochemical response (including metastable pitting analysis), hardness and crack growth rate (from SCC testing). The results revealed several important findings, indicating that there is a critical precipitate size above which a transition in electrochemical response occurs; in addition it is seen that Cu has an important role in both metastable pitting and crack propagation. The corrosion initiation and propagation phases are distinct in their mechanisms, and this is a function of the nature and state of the precipitates. Increased aging times increased the metastable pitting rate and SCC velocity in the Cu-lean alloy, whereas increased aging times decreased the metastable pitting rate the Cu-rich alloy. A correlation between metastable pitting rate and stable pitting is also presented.}, number={11}, journal={Journal of the Electrochemical Society}, author={Gupta, R.K. and Deschamps, A. and Cavanaugh, M.K. and Lynch, S.P. and Birbilis, N.}, year={2012} }
 @article{gupta_darling_singh raman_ravi_koch_murty_scattergood_2012, title={Synthesis, characterization and mechanical behaviour of an in situ consolidated nanocrystalline FeCrNi alloy}, volume={47}, ISSN={0022-2461 1573-4803}, url={http://dx.doi.org/10.1007/S10853-011-5986-6}, DOI={10.1007/s10853-011-5986-6}, number={3}, journal={Journal of Materials Science}, publisher={Springer Science and Business Media LLC}, author={Gupta, Rajeev K. and Darling, Kris S. and Singh Raman, R. K. and Ravi, K. R. and Koch, Carl C. and Murty, B. S. and Scattergood, R. O.}, year={2012}, month={Feb}, pages={1562–1566} }
 @article{hinton_behrouzvaziri_forsyth_gupta_seter_bushell_2012, title={The inhibition of hydrogen embrittlement in SAE 4340 steel in an aqueous environment with the rare earth compound lanthanum 4 hydroxy cinnamate}, volume={43}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84861882715&partnerID=MN8TOARS}, DOI={10.1007/s11661-012-1103-y}, number={7}, journal={Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science}, author={Hinton, B.R.W. and Behrouzvaziri, M. and Forsyth, M. and Gupta, R.K. and Seter, M. and Bushell, P.G.}, year={2012}, pages={2251–2259} }
 @inproceedings{gupta_hinton_hutchinson_birbilis_2011, title={A comparison of the metastable pitting response of aluminium alloys}, volume={2}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84867260268&partnerID=MN8TOARS}, booktitle={18th International Corrosion Congress 2011}, author={Gupta, R.K. and Hinton, B.R.W. and Hutchinson, C.R. and Birbilis, N.}, year={2011}, pages={1176–1182} }
 @article{gupta_singh raman_koch_2010, title={Fabrication and oxidation resistance of nanocrystalline Fe10Cr alloy}, volume={45}, ISSN={0022-2461 1573-4803}, url={http://dx.doi.org/10.1007/s10853-010-4665-3}, DOI={10.1007/s10853-010-4665-3}, number={17}, journal={Journal of Materials Science}, publisher={Springer Science and Business Media LLC}, author={Gupta, Rajeev K. and Singh Raman, R. K. and Koch, Carl C.}, year={2010}, month={Jun}, pages={4884–4888} }
 @inproceedings{gupta_raman_koch_2010, title={Processing and electrochemical corrosion resistance of a nanocrystalline Fe-20Cr alloy}, volume={1}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77952489452&partnerID=MN8TOARS}, booktitle={TMS Annual Meeting}, author={Gupta, R.K. and Raman, R.K.S. and Koch, C.C.}, year={2010}, pages={703–710} }
 @book{gupta_mahesh_raman_koch_2010, title={Processing and excellent oxidation resistance of nanocrystalline Fe-Cr alloys}, volume={654-656}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77955477425&partnerID=MN8TOARS}, DOI={10.4028/www.scientific.net/MSF.654-656.1122}, abstractNote={Nanocrystalline and microcrystalline Fe-10Cr alloys were prepared by high energy ball milling followed by compaction and sintering, and then oxidized in air for 52 hours at 400°C. The oxidation resistance of nanocrystalline Fe-10Cr alloy as determined by measuring the weight gain after regular time intervals was compared with that of the microcrystalline alloy of same chemical composition (also prepared by the same processing route and oxidized under identical conditions). Oxidation resistance of nanocrystalline Fe10Cr alloy was found to be in excess of an order of magnitude superior than that of microcrystalline Fe10Cr alloy. The paper also presents results of secondary ion mass spectrometry of oxidized samples of nanocrystalline and microcrystalline Fe-Cr alloys, evidencing the formation of a more protective oxide scale in the nanocrystalline alloy.}, journal={Materials Science Forum}, author={Gupta, R.K. and Mahesh, B.V. and Raman, R.K.S. and Koch, C.C.}, year={2010}, pages={1122–1125} }
 @inproceedings{gupta_raman_koch_2010, title={Processing and oxidation resistance of nanocrystalline Fe-10Cr alloy}, volume={2}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77952624807&partnerID=MN8TOARS}, booktitle={TMS Annual Meeting}, author={Gupta, R.K. and Raman, R.K.S. and Koch, C.C.}, year={2010}, pages={781–786} }
 @article{raman_gupta_koch_2010, title={Resistance of nanocrystalline vis-a-vis microcrystalline Fe-Cr alloys to environmental degradation and challenges to their synthesis}, volume={90}, ISSN={["1478-6443"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77954082488&partnerID=MN8TOARS}, DOI={10.1080/14786435.2010.484402}, abstractNote={This paper presents a hypothesis and its experimental validation that a nanostructure can bring about dramatic improvements in the oxidation/corrosion resistance of iron–chromium alloys. More specifically, a nanocrystalline Fe–10 wt% Cr alloy was found to undergo oxidation at a rate that was an order of magnitude lower than its microcrystalline counterpart. Importantly, the oxidation resistance of nanocrystalline Fe–10 wt% Cr alloy was comparable with that of the common corrosion-resistant microcrystalline stainless steels (having 18–20 wt% chromium). The findings have the potential of leading to the next generation of oxidation-resistant alloys. However, due to poor thermal stability of nanocrystalline structure, synthesis/processing of such alloys is a challenge. Discs of nanocrystalline Fe–10% Cr alloy were produced by ball-milling of Fe and Cr powders and compaction of the powder without considerable grain growth by processing within a suitable time–temperature window. The paper also presents a theoretical treatise to arrive at the minimum chromium content required for establishing a protective layer of chromium oxide in an Fe–Cr alloy of a given nanometric grain size.}, number={23}, journal={PHILOSOPHICAL MAGAZINE}, author={Raman, R. K. Singh and Gupta, Rajeev K. and Koch, Carl C.}, year={2010}, pages={3233–3260} }
 @article{raman_gupta_2009, title={Oxidation resistance of nanocrystalline vis-à-vis microcrystalline Fe-Cr alloys}, volume={51}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-58549099847&partnerID=MN8TOARS}, DOI={10.1016/j.corsci.2008.10.020}, abstractNote={This paper investigates the hypothesis that nanocrystalline structure may confer considerable oxidation resistance to iron–chromium alloys at much lower chromium contents. Discs of nanocrystalline Fe–10%Cr alloy were produced by ball milling of Fe and Cr powders and compaction of the powder without considerable grain growth (by processing within a suitable time–temperature window). Corrosion resistance of discs of nanocrystalline and microcrystalline alloys was compared by subjecting them to oxidation in air and post-oxidation characterisation of the oxide scales by secondary ion mass spectroscopy (SIMS). Nanocrystalline Fe–10%Cr alloy showed considerably greater oxidation resistance than the microcrystalline alloy of the same composition. Chromium content of the inner scale formed over the nanocrystalline alloy was detected to be nearly five times greater than that in the case of microcrystalline alloy, facilitating formation of the passive layer and providing an explanation for the greater oxidation of the former.}, number={2}, journal={Corrosion Science}, author={Raman, R.K.S. and Gupta, R.K.}, year={2009}, pages={316–321} }
 @inproceedings{gupta_raman_koch_2008, title={Grain growth behaviour and consolddation of ball milled nanocrystalline iron-chromium alloys}, volume={1}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-53949111826&partnerID=MN8TOARS}, booktitle={TMS Annual Meeting}, author={Gupta, R.Kr. and Raman, R.K.S. and Koch, C.C.}, year={2008}, pages={151–157} }
 @article{gupta_raman_koch_2008, title={Grain growth behaviour and consolidation of ball-milled nanocrystalline Fe-10Cr alloy}, volume={494}, ISSN={["0921-5093"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-49849092043&partnerID=MN8TOARS}, DOI={10.1016/j.msea.2008.04.019}, abstractNote={Nanocrystalline iron–chromium alloys may provide considerable corrosion resistance, even at low chromium contents. However, processing of such alloys could be a challenge. This paper describes successful synthesis of nanocrystalline Fe–10%Cr alloy by ball-milling route. In the absence of suitable hot compaction facility, the alloy powder could be successfully compacted close to the desired density, by employing a step of prior annealing of the powder. Grain growth behaviour of Fe–10%Cr nanocrystalline alloy was investigated at 500, 600 and 700 °C. At 500 °C, no appreciable grain growth was observed, after the initial grain growth. However, sudden and rapid grain growth was observed after 90 min at 600 °C, and 30 min at 700 °C.}, number={1-2}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Gupta, Rajeev and Raman, R. K. Singh and Koch, Carl C.}, year={2008}, month={Oct}, pages={253–256} }
 @inproceedings{singh raman_gupta_koch_2008, title={Low temperature oxidation of nanocystalline vis-à-vis microcrystalline Fe-Cr alloys}, volume={5}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84865012025&partnerID=MN8TOARS}, booktitle={17th International Corrosion Congress 2008: Corrosion Control in the Service of Society}, author={Singh Raman, R.K. and Gupta, R.K. and Koch, C.C.}, year={2008}, pages={3262–3269} }
 @inproceedings{singh raman rajeev_gupta_atanacio_prince_koch_2008, title={Role of micro-/nanocrystalline structure in oxidation of FE-CR alloys}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84867738362&partnerID=MN8TOARS}, booktitle={48th Annual Conference of the Australasian Corrosion Association 2008: Corrosion and Prevention 2008}, author={Singh Raman Rajeev, R.K. and Gupta, K. and Atanacio, A.J. and Prince, K. and Koch, C.C.}, year={2008}, pages={603–609} }
 @book{li_nash_brien_qiu_gupta_birbilis, title={cardiGAN: A Generative Adversarial Network Model for Design and Discovery of Multi Principal Element Alloys}, DOI={10.48550/arXiv.2202.00966}, abstractNote={Multi-principal element alloys (MPEAs), inclusive of high entropy alloys (HEAs), continue to attract significant research attention owing to their potentially desirable properties. Although MPEAs remain under extensive research, traditional (i.e. empirical) alloy production and testing is both costly and time-consuming, partly due to the inefficiency of the early discovery process which involves experiments on a large number of alloy compositions. It is intuitive to apply machine learning in the discovery of this novel class of materials, of which only a small number of potential alloys has been probed to date. In this work, a proof-of-concept is proposed, combining generative adversarial networks (GANs) with discriminative neural networks (NNs), to accelerate the exploration of novel MPEAs. By applying the GAN model herein, it was possible to directly generate novel compositions for MPEAs, and to predict their phases. To verify the predictability of the model, alloys designed by the model are presented and a candidate produced; as validation. This suggests that the model herein offers an approach that can significantly enhance the capacity and efficiency of development of novel MPEAs.}, number={2202.00966}, author={Li, Z. and Nash, W.T. and Brien, S.P. and Qiu, Y. and Gupta, R.K. and Birbilis, N} }