Micromechanical Modelling of the Superthermoelastic Behavior of Materials Undergoing Thermoelastic Phase Transition

Abstract
The superelasticity of the Shape Memory Alloys (SMA) is well known nowadays, but few models describe the non isothermal behavior of SMA. In this paper, we have developped a micromechanical modelling of the SMA's thermomechanical behavior based on a kinematical description of the strain mechanisms. In order to describe the microstructure evolution of the material, we define a thermodynamical potential in which volume fractions of the different variants of martensite used as the internal variables. This study allow us to determine the constitutive equations for the local behavior. Global one is then obtained using a scale transition method ; the self-consistent one. This model is able to predict not only the macroscopic behavior but also the evolution of the variants of martensite in the material. The results are in good agreement with experimental data and observations.