Landau Theory For Shape Memory Polycrystals

We propose a Ginzburg-Landau theory for the elastic properties of shape memory polycrystals. A single crystal elastic free energy for a system that undergoes a square-to-rectangle transformation is generalized to a polycrystal by introducing a crystal orientational field that is determined from a continuum phase field model. The coupled system is used to study domain morphology and mechanical properties of shape memory alloys in different temperature regimes.