This thesis deals with the energetic modeling of shape memory alloys.
The energy reduction reached by forming martensitic microstructures is not known exactly for phase transforming materials in the case of more than three crystallographic variants. In this work, the quality of lower bounds to the energy of
monocrystalline materials is evaluated by comparison with upper bounds. Best agreement of upper and lower bounds, and thus the most accurate estimate of the actual energy density, is achieved by second order lamination bounds taking the martensitic
twinning effect into account for better numeric efficiency.
Furthermore, polycrystalline shape memory materials are considered. In the course of this generalization of the model developed before, additional aspects such as the hysteretic stress-strain behavior as well as the influence of pre-textures caused by
the production process and the anisotropic material properties of the austenitic and martensitic variants are included.