Glass-Forming Ability and Mechanical Properties of the Ternary Cu-Zr-Al and Quaternary Cu-Zr-Al-Ag Bulk Metallic Glasses

抄録

The effects of addition of Al and equivalent atomic ratio of Ag and Al on the glass-forming ability (GFA) of the Cu₅₀Zr₅₀ alloy are investigated. It is found that the alloy with the highest GFA is the Cu₄₆Zr₄₆Al₈ alloy in ternary (Cu₅₀Zr₅₀)_100−xAl_x alloys, and the critical diameter is at least 8 mm. The simultaneous addition of Ag and Al is more effective to increase the glass-forming ability of the binary Cu₅₀Zr₅₀ alloy. The critical diameter of a glassy rod is 12 mm for the Cu₄₂Zr₄₂Al₈Ag₈ alloy. High stabilization of the supercooled liquid is the reason for high GFA of the Cu₄₆Zr₄₆Al₈ and Cu₄₂Zr₄₂Al₈Ag₈ alloys. Both glassy alloys exhibited high fracture strength above 1960 MPa, but no distinct plastic strain is seen. There is no evident difference in the mechanical properties of the as-cast Cu₄₂Zr₄₂Al₈Ag₈ glassy rods with different diameters.