Synthesis and mechanical properties of an amorphous Zr–Ni–Al–Cu alloy

Abstract

Synthesis of bulk metallic glasses (BMGs) has been one of the hottest topics of research in materials science during this decade due to their very attractive physical and mechanical properties. In the present study, Zr 64.5Ni 15.5Al 11.5Cu 8.5 alloy has been synthesized from pure elements using Cu mold-casting technique. The alloy was designed to have e/ a ratio = 1.3975 and average atomic size R a = 0.1500 nm. Thermal properties were measured by performing DSC and supercooled liquid region Δ T x was found to be 94.9 K. Mechanical properties like microhardness, nanohardness, elastic modulus and fracture strength were measured. The fracture strength was found to be ∼1988 MPa. SEM examination shows vein-like patterns in the fractured compression-tested samples. Shear bands were observed and shear angle was found to be ∼36 ± 1° which is 6° less than that for most of the bulk metallic glasses to date without addition of fifth element.