Modeling and simulation of the thermo-mechanical response of NiTi-based Belleville springs

Nickel–titanium (NiTi) Belleville washers exhibit unique mechanical and functional features due to the reversible stress-induced and/or thermally induced phase transition mechanism of NiTi alloys. In this article, the thermo-mechanical response of such washers has been analyzed by finite element simulations as well as by a special semi-analytical model, which is based on a modified literature approach. The effects of the geometrical configuration of the washers as well as of different thermo-mechanical loading conditions, under stress-induced phase transformation regime, have been analyzed. The results highlighted a marked hysteretic response, in terms of force–deflection curve, due to the hysteresis in the stress–strain behavior of NiTi alloys. In addition, a marked influence of the geometry, as well as of the temperature, has been observed on the thermo-mechanical response of the washer.