Molecular dynamics simulation of mechanical characteristics of CuZr bulk metallic glasses using uni-axial tensile loading technique

Abstract

In the present study, a three-dimensional molecular dynamics simulation is performed to elaborate the mechanical strength of bulk metallic glasses (BMGs). The radial distribution function (RDF) is used to predict the structural disorder that appeared during the quenching provided for BMGs processing. The mechanical behavior is investigated using uniaxial tensile loading through stress–strain curves. It is observed that during tensile loading, the yield strength of Cu50Zr50 increases with the increase in the strain rate, and it quickly attains the maximum value. Soon after the sample fractures without entering into the plastic region. To elucidate the effects of component concentration, we design BMGs with the following three configurations: Cu25Zr75, Cu50Zr50 and Cu75Zr25. It is revealed from the results that samples with a lower Cu concentration have a higher degree of short-range ordering and lower yield strength, and vice versa. To analyze the significance of crystalline–amorphous interfaces, we designed four cylindrical core–shell nanorods with Cu cores and BMGs shells. It is observed that the mechanical strength of the core–shell nanorod is significantly higher compared to the pure BMGs nanorod.