Solid state amorphization in binary Ti---Ni, Ti---Cu and ternary Ti---Ni---Cu system by mechanical alloying

Abstract

An amorphous phase has been synthesized by mechanical alloying in a planetary mill over a nickel content range of 10-70 at.% in the Ti---Ni system and a copper content range of 10-50 at.% in the Ti---Cu system. In the case of ternary Ti---Ni---Cu alloys the glass-forming composition range has been found to be given by x = 10-20 for Ti₆₀Ni_{40 - x}Cu_x, x = 10 - 30 for Ti₅₀Ni_{50- x}Cu_x and x = 10 - 40 for Ti₄₀Ni_{60 - x}Cu_x alloys. The difficulty in the amorphization of copper-rich compositions is explained in the light of enthalpy composition diagrams calculated for the ternary solid solution and the amorphous phase.