@article{zhang_chai_qi_wang_wu_pan_teng_murty_2023, title={Microstructures and wear resistance of Zr-4 and N36 alloys subjected to pulsed laser surface remelting}, volume={577}, ISSN={["1873-4820"]}, DOI={10.1016/j.jnucmat.2023.154284}, abstractNote={Two typical Zr alloys (Zr-4 and N36) for nuclear applications were surface-treated by laser surface remelting (LSR). Electron channeling contrast imaging and electron backscatter diffraction were used to characterize their main microstructure characteristics before and after the LSR, which were also correlated with their hardness and wear resistance. The results show that two surface modification zones with distinct microstructure characteristics appear in both the LSRed Zr alloys: (i) remelting zone (RZ) composed of fine α laths with dense internal nano-twins, and (ii) heat affected zone (HAZ) consisting of blocky α, lath α and second phase particles. The average hardness values of the RZs of Zr-4 and N36 alloys are 254.9 ± 8.5 HV and 269.5 ± 7.9 HV, respectively, ∼30% higher than their substrates. The wear rates of the LSRed Zr-4 and N36 alloys are found to be about 30% and 18% lower than their substrates, respectively, indicating significantly improved wear resistance. Comprehensive analyses reveal that refined grains, solid solution and internal nano-twins generated by ultrafast heating and cooling during the laser treatment have jointly led to the enhanced surface hardness of the LSRed Zr alloys, accounting for their improved wear resistance as well. Compared to the Zr-4 alloy, the refinement of the surface microstructure of the N36 alloy after the LSR treatment is more remarkable, contributing to higher hardness and wear resistance, which is mainly related to the addition of 1 wt.% Nb.}, journal={JOURNAL OF NUCLEAR MATERIALS}, author={Zhang, Fangli and Chai, Linjiang and Qi, Lan and Wang, Yueyuan and Wu, Lu and Pan, Hucheng and Teng, Changqing and Murty, Korukonda L.}, year={2023}, month={Apr} }
 @article{chai_xia_murty_gu_fan_yao_2022, title={Revealing Microstructural, Textural, and Hardness Evolution of Ti-6Al-4V Sheet Cooled From Sub beta-Transus Temperature at Different Rates}, ISSN={["1543-1940"]}, DOI={10.1007/s11661-022-06737-8}, journal={METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE}, author={Chai, Linjiang and Xia, Jiying and Murty, Korukonda L. and Gu, Xinfu and Fan, Jiangkun and Yao, Zhongwen}, year={2022}, month={Jun} }
 @article{chai_zhu_hu_murty_guo_chen_ma_zhang_2021, title={A strategy to introduce gradient equiaxed grains into Zr sheet by combining laser surface treatment, rolling and annealing}, volume={196}, ISSN={["1872-8456"]}, DOI={10.1016/j.scriptamat.2021.113761}, abstractNote={A novel strategy combining laser surface treatment, rolling and annealing (LST-RA) to produce gradient equiaxed grains is proposed and verified after applying to pure Zr sheet. Dense high angle boundaries (HABs) are first produced by the laser-induced rapid β→α transformation in the surface layer of pure Zr while a considerable amount of stored energy is then introduced by 50% rolling. During subsequent annealing, the preexisting denser HABs facilitate generating more recrystallization nuclei in the surface layer than in the matrix through the strain induced boundary migration mechanism. This eventually results in a gradient equiaxed grain structure from surface to interior of the pure Zr sheet. Furthermore, the fine-grained surface layer is found to have a weakened texture compared to the coarse-grained matrix.}, journal={SCRIPTA MATERIALIA}, author={Chai, Linjiang and Zhu, Yufan and Hu, Xing and Murty, Korukonda L. and Guo, Ning and Chen, Liang-Yu and Ma, Yanlong and Zhang, Lai-Chang}, year={2021}, month={Apr} }
 @article{dai_xia_chai_murty_guo_daymond_2020, title={Correlation of microstructural, textural characteristics and hardness of Ti-6Al-4V sheet beta-cooled at different rates}, volume={55}, ISSN={["1573-4803"]}, DOI={10.1007/s10853-020-04603-9}, number={19}, journal={JOURNAL OF MATERIALS SCIENCE}, author={Dai, Jiahong and Xia, Jiying and Chai, Linjiang and Murty, Korukonda L. and Guo, Ning and Daymond, Mark R.}, year={2020}, month={Jul}, pages={8346–8362} }
 @article{xiang_chai_wang_wang_guo_ma_murty_2020, title={Microstructural characteristics and hardness of CoNiTi medium-entropy alloy coating on pure Ti substrate prepared by pulsed laser cladding}, volume={849}, ISSN={["1873-4669"]}, DOI={10.1016/j.jallcom.2020.156704}, abstractNote={A ternary CoNiTi medium-entropy (MEA) alloy coating was successfully fabricated on pure Ti substrate by utilizing pulsed laser cladding. Phase constitutions and microstructural characteristics of the coating were analyzed by combined use of X-ray diffraction, electron channeling contrast imaging, secondary electron imaging, energy dispersive spectroscopy and electron backscatter diffraction techniques. Results show that three zones with distinct microstructures are formed after the pulsed laser cladding treatment: cladding zone (CZ), bonding zone (BZ) and heat-affected zone (HAZ). Dendritic (BCC solid-solution phase)-interdendritic (Ti2Ni type phase) structures are formed in the CZ with many nanoparticles (Ti2Co type phase) dispersed inside the interdendritic structures. The BZ consists of fine acicular grains while the HAZ below the BZ is composed of irregular-shaped bulk grains. Hardness measurements reveal that hardness of the MEA coating reaches 571 ± 46 H V, which is ∼5 times that of the substrate (114 ± 4 H V). Comprehensive analyses show that such high hardness can be attributed to the combined contributions from solid-solution hardening of the BCC phase and second-phase hardening from the Ti2Ni and Ti2Co type intermetallic compounds.}, journal={JOURNAL OF ALLOYS AND COMPOUNDS}, author={Xiang, Kang and Chai, Linjiang and Wang, Yueyuan and Wang, Hao and Guo, Ning and Ma, Yanlong and Murty, Korukonda L.}, year={2020}, month={Dec} }
 @article{chai_xiang_xia_fallah_murty_yao_gan_2019, title={Effects of pulsed laser surface treatments on microstructural characteristics and hardness of CrCoNi medium-entropy alloy}, volume={99}, ISSN={["1478-6443"]}, DOI={10.1080/14786435.2019.1649499}, abstractNote={ABSTRACT A hot-swaged/annealed CrCoNi medium-entropy alloy (MEA) was surface-treated by pulsed laser at two different powers (400 and 200 W). Microstructural characteristics of the laser-modified zones were characterised and analysed by energy dispersive spectroscopy, electron backscatter diffraction and electron channelling contrast imaging techniques. Results show that melting and rapid solidification occur on the surfaces of both laser-treated specimens, and profuse annealing twins existing in the initial microstructures are essentially eliminated in the melting zone (MZ) with plentiful low-angle boundaries appearing. Meanwhile, the initial equiaxed grains are replaced by new grains in the MZ with either granular or columnar appearance (in the 2D cross-sectional views). These grains are comprised of fine cellular structures with relatively uniform sizes (∼1–2 μm in width/diameter), the formation of which is related to the segregation of Cr during solidification. With the laser power decreasing from 400 to 200 W, the volume of the MZ and grain sizes in its interior are reduced. This is due to less heat supply and faster cooling caused by reducing the laser power. Hardness tests reveal that the surfaces of both the laser-treated specimens are slightly softened (by 10–20%), and quantitative analyses suggest that this is mainly related to grain coarsening and the disappearance of annealing twins in the MZ.}, number={24}, journal={PHILOSOPHICAL MAGAZINE}, author={Chai, Linjiang and Xiang, Kang and Xia, Jiying and Fallah, Vahid and Murty, Korukonda L. and Yao, Zhongwen and Gan, Bin}, year={2019}, month={Dec}, pages={3015–3031} }
 @article{chai_luan_zhang_murty_liu_2013, title={Experimental observation of 12 alpha variants inherited from one beta grain in a Zr alloy}, volume={440}, ISSN={["1873-4820"]}, DOI={10.1016/j.jnucmat.2013.05.053}, abstractNote={Local crystallographic orientation characteristics of a Zr alloy after β cooling are investigated by electron backscatter diffraction (EBSD) technique. All misorientation peaks and corresponding rotation axes predicted by Burgers relationship are exclusively verified for the obtained basket-weave structure. Furthermore, by correlating microstructures and crystallographic orientations, all 12 possible α variants inherited from one prior β grain are definitely revealed. It is believed that excessive β grain growth in the Zr alloy is responsible for the weak or absence of variant selection during β cooling.}, number={1-3}, journal={JOURNAL OF NUCLEAR MATERIALS}, author={Chai, Linjiang and Luan, Baifeng and Zhang, Min and Murty, Korukonda L. and Liu, Qing}, year={2013}, month={Sep}, pages={377–381} }
 @article{chai_luan_murty_liu_2013, title={Twinning during recrystallization cooling in alpha-Zr alloy}, volume={576}, ISSN={["1873-4936"]}, DOI={10.1016/j.msea.2013.04.010}, abstractNote={Recently, twinning induced by intergranular thermal residual stresses (ITRSs) has been first reported in a Zr alloy after β→α furnace cooling. To further explore this kind of twinning behavior, microstructures and textures of the Zr alloy during α annealing between 650 and 750 °C after β quenching were investigated in the present work, by use of X-ray diffraction, electron backscatter diffraction and electron channeling contrast imaging techniques. Results indicate that the ITRS-induced twins could also occur during cooling after α-recrystallization annealing in the Zr alloy, closely related to both the grain size and the texture. When the recrystallization texture is relatively random, high tensile ITRSs up to ~200 MPa along c-axis could be accumulated. Tensile twins can only be induced by the tensile ITRS in the nearly texture-free Zr specimen with an average grain size larger than ~20 μm.}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Chai, Linjiang and Luan, Baifeng and Murty, Korukonda L. and Liu, Qing}, year={2013}, month={Aug}, pages={320–325} }