Microhardness of Sb2Te3 - Bi2Te3 solid solutions

Sb2Te3 - Bi2Te3 semiconducting solid solutions are presently the best low-temperature thermoelectric materials, which are extensively used in manufacturing refrigerant devices of different types. The dependences of their thermoelectric and other properties on the solid solution composition were investigated in a number of works [1]. As far as the mechanical properties are concerned, in particular microhardness H, mainly pure Sb2Te3 and Bi2Te3 and the compositions corresponding to the maximum thermoelectric efficiency values (∼ 25mol.% Bi2Te3) [2,3] were investigated. There is no information available on the concentration dependences of H in the range of the small impurity content. Meantime, mechanical properties are important for designing thermoelectric devices.