Background of Two Characteristic Features of Shape Memory Phenomena

The changes of Young ’s moduli accompanying martensitic transformation of binary shape memory (SM) alloys are explained on the basis of potentials of interatomic forces, and their shifts due to temperature changes. It is shown that not only qualitative, but even approximate quantitative agreement between such an explanation and experimental findings can be received if working with 3D analysis. On the basis of this concept, a mathematical model with tensorial internal variables for the description of thermomechanical behavior of binary SM alloys has been formulated. It is now shown that our model has a very important property that is generally observed and recognized - the linear relation between temperature and threshold stress level necessary for stress-induced martensite.