Thermomechanical model for NiTi-based shape memory alloys covering macroscopic localization of martensitic transformation

The work presents a thermomechanical model for polycrystalline NiTi-based shape memory alloys developed within the framework of generalized standard solids, which is able to cover loading-mode dependent localization martensitic transformation. key point introduction novel austenite–martensite interaction term responsible strain-softening material. Mathematical properties are analyzed, and suitable regularization time-discrete approximation numerical implementation finite-element method proposed. Model performance illustrated on two simulations: tension superelastic NiTi ribbon bending tube.