Temperature distribution due to localised martensitic transformation in SMA tensile test specimens

Due to the thermoelastic nature of the austenite–martensite phase transformation in the pseudoelastic temperature range the mechanical response of a polycrystalline NiTi specimen strongly depends on the thermal boundary conditions of the experimental setup. In uniaxial tensile tests the transformation is inhomogeneous and localised in bands with moving transformation fronts. The latent heat of the transformation leads to a local increase of the temperature near the moving front. Analytical solutions for the moving heat source problem will be derived for adiabatic conditions as well as for the case of heat transfer at the surface of the specimen.