Improvement of Glass Forming Ability of Cu-Ni-Zr-Ti Alloys by Substitution of Hf and Nb

Abstract

New bulk metallic glasses exhibiting a high glass forming ability were formed by a substitution of Hf and Nb for Zr and Ti in quaternary Cu-Ni-Zr-Ti system. An 8 mm-diameter BMG rod was obtained at the Cu₅₀Ni₈Zr₁₅Hf₃Ti₂₃Nb₁ composition by suction casting method. The glass transition temperature, crystallization temperature and reduced glass transition temperature of the BMG were 699 K, 754 K, and 0.59, respectively. Making an alloy system more complex was useful to increase the GFA.