基于TiNi合金的超弹性对其相关磨损机制的FEM研究

本文在重点考虑TiNi合金高弹性变形量的前提下，采用等向强化模型，对不锈钢和超弹TiNi合金在法向接触载荷作用下的六种模型进行了有限元(FEM)分析。结果表明：在相同载荷条件下，超弹TiNi合金产生的von Mises弹性应变要高于不锈钢，但其von Mises应力和塑性应变却恰恰相反，在同一载荷下该合金发生塑性变形的区域要小于不锈钢；此外，超弹TiNi合金发生塑性变形要比不锈钢困难，所需的临界载荷值随其最大弹性变形量(屈服点处的应变值)的增加而增加。最后，基于本文的有限元计算结果对超弹TiNi合金的蘑粒磨损和疲劳磨损机制进行了讨论。

Finite Element Analysis of Pseudoelastic TiNi Alloys under Normal Contact Load Based on the Isotropic Hardening Model

In this paper, on the premise of considering the high capability of elastic deformation of TiNi alloys mainly the isotropic hardening model was adopted to analyze six models of pseudoelastic TiNi alloys and the stainless steel under normal contact loads using a finite element method(FEM). Results showed that:Under the same load, the maximum von Mises elastic strains of pseudoelastic TiNi alloys were higher than those of the stainless steel, but the maximum von Mises stresses and maximum von Mises plastic strains were even on the contrary, and the plastic zones were also smaller than those of the stainless steel. For pseudoelastic TiNi alloys, it was harder to create plastic deformation than the stainless steel, and the critical load of the plastic deformation increased with the increasing the maximum elastic deformation(the strain value at the yield point)of the material. Finally, the mechanisms of the particle and fatigue wear of pseudoelastic TiNi alloys were discussed based on results of the finite element computation.