In-situ Ta-rich particle reinforced Zr-based bulk metallic glass matrix composites with tensile plasticity

Abstract

In-situ Ta-rich particle reinforced Zr-based bulk metallic glass matrix composite has been successfully fabricated by doping Ta. The dispersion of Ta-rich particles was quite homogenous. The size and inter-particle spacing of the Ta-rich particles were very close to the plastic processing zone size. By varying the doping amount of Ta, the volume fraction of Ta-rich particles can be tailored. Furthermore, the bonding between Ta-rich particle and glassy matrix seemed to be strong for the lack of oxide or compound layer at the interfaces. With more Ta-rich particles, the composites show better mechanical properties, including higher fracture strength and larger plastic strain. The Ta-rich particles can hinder the rapid propagation of main shear band, generating multiple shear bands. Smaller value of average stress drop after yielding for the composites with more Ta doping indicates lower formation energy of shear bands, which links to the better plasticity. The deformation of Ta-rich particle itself also contributes to the plasticity and hardening behavior of the composite. The composite with 10 at.% Ta doping even shows ∼2% plastic strain under tension.