In this work, the eXtended finite element method (XFEM) is implemented for the multiphysics analysis of edge dislocations near a heterostructure (bi-material) interface with nonuniform misfit strain. A novel enrichment is defined to incorporate the singular behavior of the electric potential due to dislocation. Nonlinear material properties due to temperature are taken for a thermo-electro-elastic analysis. The constituting materials having different lattice parameters result in a mismatch–misfit​ strain near the interface. This nonuniform misfit strain distribution affects the dislocations near the bi-material interface. Volterra dislocation modeling is performed to obtain all the primary and secondary fields around dislocations. An expression of the Peach–Koehler force considering the combined effect of the multiple fields is proposed. The results are obtained when the misfit strain is present on one side of the interface and both sides of the interface. A comparative study is performed on the Peach–Koehler force obtained in different cases of the misfit consideration with the case when the misfit strain is absent. Also for the case when the misfit strain is taken on the same side of the interface, the Peach–Koehler force is obtained by varying the misfit percentages corresponding to the different amounts of misfit relaxation.

在这项工作中，采用扩展有限元法 (XFEM) 对具有非均匀失配应变的异质结构（双材料）界面附近的边缘位错进行多物理场分析。一种新的富集被定义为结合由于位错引起的电势的奇异行为。由温度引起的非线性材料特性被用于热电弹性分析。具有不同晶格参数的构成材料会导致界面附近出现失配-错配应变。这种不均匀的失配应变分布会影响双材料界面附近的位错。执行 Volterra 位错建模以获得位错周围的所有初级和次级场。提出了考虑多个场的综合影响的 Peach-Koehler 力表达式。当失配应变存在于界面的一侧和界面的两侧时获得结果。对在考虑失配的不同情况下与不存在失配应变的情况下获得的 Peach-Koehler 力进行了比较研究。同样对于在界面的同一侧采取失配应变的情况，通过改变对应于不同失配松弛量的失配百分比来获得 Peach-Koehler 力。