Role of tensile elastostatic loading on atomic structure and mechanical properties of Zr55Cu30Ni5Al10 bulk metallic glass

Abstract

In this work, the pre-tensile elastostatic loading with low stress values (5%–20% σy) was used to rejuvenate Zr55Cu30Ni5Al10 bulk metallic glass (BMG). The atomic pair density function analysis shows that the rejuvenation evolution is accompanied with a significant disordering of short and medium atomic scales in the BMG structure. The results also indicate that the decreasing rate of annihilation in CuZr pairs under rejuvenation is higher than ZrZr and ZrAl pairs. In general, it is suggested that the interaction of stress domains under elastostatic loading is the main reason for disordering during the rejuvenation evolution. The compression test reveals that a brittle-to-ductile transition is happened from as-cast sample to the rejuvenated ones. Moreover, it is found that the serrations in the plastic region of stress-strain curves of highly-rejuvenated samples show a self-organized critical state. As a whole, with increase in pre-tensile elastostatic loading value, the structural rejuvenation enhances and the homogeneous plasticity improves.