Fabrication of functionally graded thermoelectric coatings by plasma spraying of mechanically-alloyed composite powders

摘要

Functionally graded structure is regarded as the effective system for thermoelectric conversion(TEC) mateirial. IN this study, homogeneously mixed metal/metal composite powders made by mechanical alloying(MA) were applied to plasma spraying to obtain the intermetallic TEC coatings, and the process conditions for getting the high performance TEC coatings were investigated. Consequently, optimum conditions of mechanical alloying, plasma spraying and post heat treatment to get the appropriate thermoelectric phases for each material system were empirically decided. As the fundamental reseach for the functionally graded TEC coating, the joint type Si-Ge coating with different dopant compositions was applied to be fabricated and the thermoelectric property of the joint was evaluated.