@article{guduru_darling_scattergood_koch_murty_bakkal_shih_2006, title={Shear punch tests for a bulk metallic glass}, volume={14}, ISSN={["1879-0216"]}, DOI={10.1016/j.intermet.2006.01.052}, abstractNote={A shear punch test technique was used for characterization of the mechanical properties of Zr–5Ti–17.9Cu–14.6Ni–10Al bulk metallic glass. The ultimate shear stress values matched very closely with values derived from uniaxial compression tests reported in the literature. This is consistent with a lack of pressure sensitivity in compression reported for this particular metallic glass. Deformation response was strain rate insensitive up to a critical rate, beyond which softening occurred. The latter was attributed to thermal heating effects.}, number={12}, journal={INTERMETALLICS}, author={Guduru, R. K. and Darling, K. A. and Scattergood, R. O. and Koch, C. C. and Murty, K. L. and Bakkal, M. and Shih, A. J.}, year={2006}, month={Dec}, pages={1411–1416} }
 @article{bakkal_shih_mcspadden_liu_scattergood_2005, title={Light emission, chip morphology, and burr formation in drilling the bulk metallic glass}, volume={45}, ISSN={["1879-2170"]}, DOI={10.1016/j.ijmachtools.2004.11.004}, abstractNote={The chip light emission, chip morphology, burr formation and machined surface in drilling of Zr-based bulk metallic glass (BMG) material are investigated. This study demonstrates that the work- and tool-material as well as the feed rate and spindle speed, two drilling process parameters, all affect the onset of chip light emission. Slow feed rate and high spindle speed increase the specific cutting energy and promote the exothermic oxidation and light emission of the chip. Six types of chip morphology, powder, short ribbon, long ribbon, long spiral, long ribbon tangled, and fan, are observed in BMG drilling. The long ribbon tangled chip morphology is unique for BMG material. On the machined surface under quick stop condition, the fracture topography unique to metallic glass with tributary, void, and vein patterns is observed. Different burr formations are observed: the roll-over shape in the entry and the crown shape in the exit edge. The size of burr in the exit edge is typically larger than that in the entrance edge. High feed rate helps to reduce the size of burr in both entrance and exit edges. This study concludes that the WC–Co tool-material, due to its high thermal conductivity and hardness, performs better in drilling BMG than the high speed steel tool.}, number={7-8}, journal={INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE}, author={Bakkal, M and Shih, AJ and McSpadden, SB and Liu, CT and Scattergood, RO}, year={2005}, month={Jun}, pages={741–752} }
 @article{bakkal_shih_mcspadden_scattergood_2005, title={Thrust force, torque, and tool wear in drilling the bulk metallic glass}, volume={45}, ISSN={0890-6955}, url={http://dx.doi.org/10.1016/j.ijmachtools.2004.11.005}, DOI={10.1016/j.ijmachtools.2004.11.005}, abstractNote={The thrust force, torque, and tool wear in drilling of Zr-based bulk metallic glass (BMG) material are investigated. Drilling the BMG at high speed generates the chip light emission, high tool temperature, and severe tool wear. At low spindle speed, the BMG work-material builds up at the major and margin cutting edges and may break the drill. A range of feasible spindle speed and feed rate for the efficient drilling of BMG without the detrimental chip light emission and cutting edge work-material build-up has been identified in this study. Under the same drilling condition, the WC-Co tool generally requires less thrust force and about the same torque than the high-speed steel tool. The progressive wear of the major and margin cutting edges for BMG drilling is examined. Severe drill wear is associated with the bright BMG chip light emission. Without chip light emission, the drill wear is visible but not severe. This study concluded that precision holes in BMG could be generated with proper selection of tooling and process parameters.}, number={7-8}, journal={International Journal of Machine Tools and Manufacture}, publisher={Elsevier BV}, author={Bakkal, Mustafa and Shih, Albert J. and McSpadden, Samuel B. and Scattergood, Ronald O.}, year={2005}, month={Jun}, pages={863–872} }
 @article{bakkal_shih_scattergood_2004, title={Chip formation, cutting forces, and tool wear in turning of Zr-based bulk metallic glass}, volume={44}, ISSN={["1879-2170"]}, DOI={10.1016/j.ijmachtools.2004.02.002}, abstractNote={The chip light emission and morphology, cutting forces, surface roughness, and tool wear in turning of Zr-based bulk metallic glass (BMG) material are investigated. Machining results are compared with those of aluminum 6061-T6 and AISI 304 stainless steel under the same cutting conditions. This study demonstrates that the high cutting speeds and tools with low thermal conductivity and rake angle activate the light emission and chip oxidation in BMG machining. For the BMG chip without light emission, serrated chip formation with adiabatic shear band and void formation is observed. The cutting force analysis further correlates the chip oxidation and specific cutting energy and shows the significant reduction of cutting forces for machining BMG at high cutting speeds. The machined surface of BMG has better surface roughness than that of the other two work materials. Some tool wear features, including the welding of chip to the tool tip and chipping of the polycrystalline cubic boron nitride (PCBN) tool edge, are reported for turning of BMG. This study concludes that BMG can be machined with good surface roughness using conventional cutting tools.}, number={9}, journal={INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE}, author={Bakkal, M and Shih, AJ and Scattergood, RO}, year={2004}, month={Jul}, pages={915–925} }
 @article{bakkal_shih_scattergood_liu_2004, title={Machining of a Zr-Ti-Al-Cu-Ni metallic glass}, volume={50}, ISSN={["1359-6462"]}, DOI={10.1016/j.scriptamat.2003.11.052}, abstractNote={Zr52.5Ti5Cu17.9Ni14.6Al10 metallic glass machining chips were characterized using SEM, X-ray diffraction and nano-indentation. Above a threshold cutting speed, oxidation of the Zr produces high flash temperatures and causes crystallization. The chip morphology was unique and showed the presence of shear bands, void formation and viscous flow.}, number={5}, journal={SCRIPTA MATERIALIA}, author={Bakkal, M and Shih, AJ and Scattergood, RO and Liu, CT}, year={2004}, month={Mar}, pages={583–588} }
 @article{bakkal_liu_watkins_scattergood_shih_2004, title={Oxidation and crystallization of Zr-based bulk metallic glass due to machining}, volume={12}, DOI={10.1016/j.internet.2003.09.017}, number={2}, journal={Intermetallics}, author={Bakkal, M. and Liu, C. T. and Watkins, T. R. and Scattergood, R. O. and Shih, A. J.}, year={2004}, pages={195–204} }