Strain rate and temperature effect on Zr50Cu50 metallic glass under pure shear

Abstract

We present a molecular dynamics study of the mechanical properties of Zr50Cu50 glass under pure shear. The samples have 145.200 atoms with dimensions of 40 × 20 × 2 nm in the x, y and z directions, respectively. After quenching, we obtain 3 different systems at temperatures of 10, 50, 300 K. All systems were then subjected to dynamic pure shear at constant shear rates of 2.5×108 s-1, 5×108 s-1 and 2.5×109 s-1. We investigate the changes of mechanical properties as a function of temperature and shear rate, and find that the shear modulus is not sensitive to the changes of the shear rate, but decreases as the temperature rises. Ultimate strength is enhanced at higher shear rates and decreases with temperature. A study of the atomic structure reveals that the low values of ultimate strength are associated with high values of local atomic shear strain. These results are reminiscent of what happens at the jamming transition.