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arXiv · 1912.01356

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

M. Frost·B. Benešová·H. Seiner·M. Kružík·P. Šittner·P. Sedlák
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Abstract

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 of the martensitic transformation. The key point is the introduction of a novel austenite-martensite interaction term responsible for strain-softening of the material. Mathematical properties of the model are analyzed and a suitable regularization and a time-discrete approximation for numerical implementation to the finite-element method are proposed. Model performance is illustrated on two numerical simulations: tension of a superelastic NiTi ribbon and bending of a superelastic NiTi tube.

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M. Frost, B. Benešová, H. Seiner, M. Kružík, P. Šittner, P. Sedlák. 2019-12-03. Thermomechanical model for NiTi-based shape memory alloys covering macroscopic localization of martensitic transformation. https://doi.org/10.1016/j.ijsolstr.2020.08.012

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