Elastic moduli of a ZrCuAlNi bulk metallic glass from room temperature to complete crystallisation by in situ pulse-echo ultrasonic echography

Abstract

An in situ ultrasonic echography technique is used to follow the changes in the elastic moduli (Young's modulus and shear modulus) from room temperature to complete crystallisation temperature (~900 K) of a ZrCuAlNi bulk metallic glass. Elastic moduli changes allow to probe the structural transformations of the alloy below and above the glass transition as well as the crystallisation stages. Of peculiar interest is the unusual decrease in Poisson's ratio.