Excellent combination of strength and ductility in CoNiCr-based MP159 alloys at cryogenic temperature

Abstract

In this study, a multi-component single-phase CoNiCr-based MP159 alloy with a high dislocation density is investigated when subjected to cold rolling. The alloy has an ultra-high yield strength of 1807 MPa and large ductility of more than 20% at 77 K, with a significant temperature dependence. The difference in mechanical properties between cryogenic and room temperatures is illustrated by the analysis of the deformation structures, and the deformation twinning is found to make an critical contribution to high strength and large ductility. It provides an alternative way to strengthening metallic materials in the current investigation.