Mechanical properties of Bi _xSb _2-xTe ₃ nanostructured thermoelectric material

Research on thermoelectric (TE) materials has been focused on their transport properties in order to maximize their overall performance. Mechanical properties, which are crucial for system reliability, are often overlooked. The recent development of a new class of high-performance, low-dimension thermoelectric materials calls for a better understanding of their mechanical behavior to achieve the desired system reliability. In the present study we investigate the mechanical behavior of nanostructure bulk TE material p-type Bi _xSb _2xTe ₃ by means of nanoindentation and 3D finite element analysis. The Youngs modulus of the material was estimated by the OliverPharr (OP) method and by means of numerically assisted nanoindentation analysis yielding comparable values about 40GPa. Enhanced hardness and yield strength can be predicted for this nanostructured material. Microstructure is studied and correlation with mechanical properties is discussed.