Thermoelectric Performance of Half-Heusler TiNiSn AlloysFabricated by Solid-Liquid Reaction Sintering

摘要

A new fabrication process was proposed for half-Heusler type TiNiSn thermoelectric alloys.Based on the result that the TiNiSn phase can be formed easily at the Sn(Liquid)/TiNi(Solid) interface,the liquid-solid reaction-sintering process was developed using TiNi and Sn powders. The TiNicompound powders were prepared by the atomization method using argon gas atmosphere. We havefabrictaed nearly single-phase TiNiSn alloys and evaluated their thermoelectrical properties; thepresnt TiNiSn alloys have large electrical power factor of about 3.5 mWm~(-1)K~(-2),and the maximumvalue of dimensionless figure of merit, ZT = 0.67, can be achieved at around 700 K even withouttuning of the carrier concentration through alloying elements.