Plasticity Enhancement of an Amorphous Alloy Driven by Atomistic-scale Phase Separation

摘要

A bulk amorphous alloy, Zr_(54)Cu_(36)Al_4Be_6, was synthesized. This alloy shows a yield strength of approx 1.8 GPa and a large plastic strain of approx 20.5 percent, which have hardly been observed in monolithic bulk amorphous alloys. Microstructures of this alloy were observed to investigate the origin of the extraordinary plasticity of the alloy. The alloy exhibited a unique microstructure characterized by atomistic-scale phase separation, which probably stems from the large difference in mixing enthalpy between the binary pairs of Zr-Be and Cu-Be. This paper discusses the effect of atomistic-scale phase separation on the enhanced plasticity of amorphous alloys.