Fracture toughness of thermoelectric materials

The engineering applications of thermoelectric (TE) devices require TE materials possessing high TE performance and robust mechanical properties. Research on thermal and electrical transport properties of TE materials has made significant progress during the last two decades, developing TE materials on the threshold of commercial applications. However, research on mechanical strength and toughness has lagged behind, restricting application of TE materials. Mechanical failure in these materials involves multi-scale processes spanning from atomistic scale to macro scale. We have proposed an integral stress-displacement method to estimate fracture toughness from intrinsic mechanical behavior. In this review, we summarize our recent progress on fracture toughness of TE materials. This is in three parts: