Formation of ductile Cu-based bulk metallic glass matrix composite by Ta addition

Abstract

The Effect of the Ta addition on the fabrication of the ductile phase reinforced Cu-Zr-Ti bulk metallic glass (BMG) matrix composite was investigated. A composite microstructure consisted of pm-scale Ta-rich solid solution particles distributed in the BMG matrix was successfully obtained by injection casting of the (Cu60Zr30Ti10)(95)Ta-5 alloy into a copper mold. Ta-rich solid solution particles were observed to form first in the liquid melt during solidification, while the remaining melt solidified into the amorphous phase at lower temperature. The monolithic Cu60Zr30Ti10 BMG shows a compressive strength of 2080MPa and a fracture strain of 3.3%, while the (Cu60Zr30Ti10)(95)Ta-5 BMG matrix composite shows compressive strength of 2320MPa and, in particular, a significantly improved plastic strain to failure of about 14.5%. The remarkable ductility improvement in the (Cu60Zr30Ti10)(95)Ta-5 composite could be explained by the presence of the highly ductile Ta-rich particles.