Developments of eco-friendly silicide-based thermoelectric materials using powder metallurgical processes

Both of high performance and low cost of the thermoelectric materials are required for the practical use of a thermoelectric power generation using waste heat. The silicide-based thermoelectric materials constituted of the eco-friendly raw materials that are less toxic and abundant in the earth's crust has been attracting attention. In this study, material developments of the dimagnesium suicide (Mg2Si) and the higher manganese suicide (HMS) have been carried out for high thermoelectric performance using powder metallurgical processes. The Mg2Si compounds were synthesized via the liquid-solid phase reaction process and consolidated by pulse discharge sintering. For production of the HMS compounds, a series of processes of pulverization, mixing and pulse discharge sintering was used. Various synthesizing conditions were attempted for improving the thermoelectric performance of these materials.