Correlation between entropy and glass-forming ability of Cu-Zr and Cu-Zr-Al alloys

Excess entropy and mismatch entropy in CuxZr100-x (46 < x < 70) and Cu50Zr50-xAlx (5 < x < 40) alloys have been obtained using an analytical thermodynamic approach based on hard-sphere model for the structure of liquids. The atomic packing efficiency is an important input parameter in this approach and is usually taken to be 0.64 for all the metallic systems. In this study, classical molecular dynamics simulations have been performed to obtain the packing efficiency by analyzing the three-dimensional microscopic structure of metallic alloys. The compositional dependence of the entropies in Cu-Zr alloys show a good correlation with the glass-forming ability and, it is consistent with the experimental and simulation results. For Cu-Zr-Al alloys, the variation in the entropies with the composition does not indicate an unambiguous correlation with glass-forming ability. However, these results provide useful insights of the effect of substitution of Zr by Al on the glass-forming ability. (c) 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the Recent Advancements in Materials science And Nanotechnology conference.