New Class of Plastic Bulk Metallic Glass

Abstract

An intrinsic plastic ${\mathrm{Cu}}_{45}{\mathrm{Zr}}_{46}{\mathrm{Al}}_{7}{\mathrm{Ti}}_{2}$ bulk metallic glass (BMG) with high strength and superior compressive plastic strain of up to 32.5% was successfully fabricated by copper mold casting. The superior compressive plastic strain was attributed to a large amount of randomly distributed free volume induced by Ti minor alloying, which results in extensive shear band formation, branching, interaction and self-healing of minor cracks. The mechanism of plasticity presented here suggests that the creation of a large amount of free volume in BMGs by minor alloying or other methods might be a promising new way to enhance the plasticity of BMGs.