Plasma spray forming as a novel production method for thermoelectric materials

Abstract

To date the development of thermoelectric materials and technology has reached a level, that allows the fabrication of reliable generators. It now turns out that the main impediment on the way to large scale, commercial (terrestrial) applications is primarily not the comparable low efficiency of the devices, but the high investment costs, which are still on the order of several ten Dollars per Watt. Necessary conditions for cost reduction are the availability of (i) cheap, non-toxic materials in large quantities and (ii) processing methods which allow efficient production; preferably the formation of complete device structures within a single, automized manufacturing step. This paper introduces plasma spraying as a forming process with the potential to fulfil the above stated condition. The paper reports on first studies on the consolidation and characterization of iron disilicide (FeSi/sub 2/). It was found that plasma spray forming is applicable to produce dense materials with properties comparable to hot-pressed ones.