The Use of Fracture Mechanics Analysis in the Design and Development of Thermoelectric Cells

The challenge of designing a conduction-coupled thermoelectric cell has been met through the use of fracture mechanics analysis. Thermoelectric cells consist of multiple layers of brittle materials bonded together at high temperatures. Thermal stresses develop as these devices are cooled to room temperature due to the mismatch between the coefficients of thermal expansion of the various materials. If the mismatch stress is too great, catastrophic cracking occurs. Recent developments in the fracture mechanics area have led to the development of a finite element analysis design tool that can accurately predict both when and where cracking will occur. This design tool can now be used to design thermoelectric cells that will survive the severe manufacturing environment.