Temperature and thermal stress around an elliptic functional defect in a thermoelectric material

Abstract

Functional defect leads to high temperature as well as considerable thermal stress in thermoelectric materials, which is one of the major reliability failure mechanisms of thermoelectric devices. In this perspective, the thermal-electric-elastic fields around an elliptic functional defect in a two-dimension thermoelectric plate is analyzed based on the complex variable method, and the field distributions have been obtained in closed-form. The results show that the temperature at the defect tip increases with the defect size, and can surpass the temperature at the hot end and even exceed the material melt point. Besides, both the von Mises stresses within the matrix and defect can exceed the yield stresses of many materials. These results can be used for the fracture study and reliability analysis of thermoelectric materials.