A three-dimensional model describing stress-induced solid phase transformation with permanent inelasticity

The employment of shape memory alloys (SMA) in a large number of applications in the fields of aeronautical, biomedical, and structural engineering has been the motivation for an increasing interest in the direction of a correct and exhaustive modeling of their macroscopic behaviour. Many models for SMA available in the literature consider fully reversible phase transformations (i.e. no permanent inelastic strains), which are proved by experiments to be sometimes a not fully realistic approximation. In this paper we propose a new three-dimensional model which is capable of including permanent inelastic effects combined with a good description of pseudo-elastic and shape-memory behaviours. Moreover, we report the numerical results from a number of both uniaxial and non-proportional biaxial tests, which aim at assessing model features and performance.