High Temperature Mechanical Properties of Rapidly Quenched Zr50Ni27Nb18Co5 Amorphous Alloy

Abstract

The high temperature mechanical properties of Zr50Ni27Nb18Co5 amorphous ribbons, proposed as metallic membrane material for hydrogen purification are presented. The mechanical behavior of the amorphous alloy, which generally does not exhibit a super-cooled liquid region, can be categorized into varying temperature regimes. A strain rate dependent phenomenon was observed between 425 degrees C < T < 490 degrees C in the strain rate range of 10(-6)s(-1) to 10(-2)s(-1). However, the alloy did not exhibit Newtonian-flow characteristics at the varied test temperature and strain rate range employed in this study. Detailed analyses indicated that in these temperature regimes structural changes occur, resulting in the formation of nanocrystalline phases. The results from these mechanical tests corroborated with the microstructural changes that occurred at these temperatures/strain rates.