Understanding the Transformation Behaviour of Metastable Beta Alloys

Abstract

Metastable β alloys that are able transform to the αʺ martensite can recover large macroscopic strains through shape memory or superelastic behaviours. This ability, combined with their high specific strengths and low stiffnesses make them very attractive for a broad range of industrial applications. However, despite substantial research, obtaining reliable and repeatable transformation properties remains challenging and often the observed behaviour cannot be rationalised by existing transformation theories. Here, we introduce a new approach to describing the transformation and show that internal stresses have a significant influence on this behaviour.