In-situ observations of reversible martensitic transformations in shape memory alloys

The conditions of performing in-situ TEM and OM straining and in-situ TEM heating experiments with CuAlMn and TiNiCu shape memory alloys were discussed. It was shown that correlating the bulk straining tests with in-situ straining experiments allow to determine the strain temperature phase diagrams for CuAlMn martensitic phases. The in-situ heating experiments helped to explain the influence of different elements of microstructure, like grain size, precipitates or dislocations in TiNiCu alloy on nucleation and grow of martensite.