Studies on mechanical properties of thermoelectric materials by nanoindentation

Abstract

In order to fabricate durable and efficient thermoelectric generators (TEG) for applications like automobile waste heat recovery, where thermal stress is a major concern, one needs to assess the mechanical performance of the TE materials. This work reports the hardness and elastic modulus of the moderate temperature range (200–1000 °C) TE materials, including half‐Heusler, skutterudites, bismuth telluride, silicon germanium alloys, and lead selenide, using nanoindentation and atomic force microscopy (AFM). The p‐type half‐Heusler exhibits considerably higher hardness and modulus values, and lower brittleness as compared with other materials, which may be indicative of its more robust mechanical performance.