Thermomechanical representation of shape memory behaviour

In this article we propose a material model for the representation of shape memory behaviour based on a phenomenological thermoviscoplasticity theory. The constitutive model is thermodynamically consistent in the sense of its compatibility with the Clausius-Duhem inequality as a special formulation of the 2nd law of thermodynamics. Numerical solutions of the constitutive equations for isothermal and nonisothermal strain and stress-Processes demonstrate that the behaviour of these materials, namely the one-and two-way shape memory effect, the pseudoelasticity and the pseudoplasticity as well as the transition region between pseudoelasticity and pseudoplasticity, is depicted as observed.