Thermal treatments and effect of electrothermal aging on the evolution of phase transformation of Ti-Ni Alloys

The processing to which a material is submitted is capable to modify its mechanical resistance. Ti-Ni wires obtained by die drawing conformation process exhibit a high density of defects. The reconfiguration of these defects allows the development of changes on the martensitic transformation. This study analyzes the behavior on the martensitic and rhombohedral phase transformation in Ti-Ni alloys due to heat treatment and electrothermal effect. The calorimetric characterization technique (DSC) was used to investigate the phase transformation behavior of the material and X-ray diffraction was used to identify the phases formed due to this procedure. The performance evaluation of the material through different heat treatment and electrothermal conditions is important when you want to use Joule effect to activate actuators for a large period of time. These conditions may lead to modification of the transformation temperatures, as well as the actuator degradation. (author)