The Influence of Increasing Copper Addition on the Properties of (NiCu)ZrTiAlSi Amorphous Alloys

摘要

Ni based BMGs with Cu addition may form a composite structure containing particles (dendrites) of a ductile phase in an amorphous matrix. Alloys of (Ni_1-xCu_x)₆₀(Zr₁₈Ti₁₃)Al₅Si₄ composition, with copper content increasing from 8 to 23 at.% were investigated in the form of ribbons produced by melt spinning and bulk samples solidified in a copper mould. Increasing Cu content resulted in gradually decreasing melting, glass transition and primary crystallization temperatures, while supercooled liquid range DT increased. The microhardness and Young modulus of the ribbons slightly decreased with the Cu content increase. The 0.65 value of the reduced glass transition temperature remained independent of the Cu addition. Bulk samples underwent partial crystallization of the dendrites. The lowest amorphous phase amount revealed the alloy with 25 at.% of the Cu addition.