Tuesday, May 22, 2012: 4:00 PM
Room 336 AB (Hilton Americas Houston )
Magnesium silicide is a narrow band gap semiconductor with a face-centered cubic structure. It is a non-toxic material and as such, is a candidate thermoelectric material for operation in the temperature range from 500 to 800 K. In this paper, air plasma spraying (APS) was used to prepare Mg2Si coating and its functional properties were evaluated to examine the coating’s feasibility as a thermoelectric power generator material. During spraying, in-flight particle temperature and velocity with different conditions were measured via DPV-2000 particle diagnostics system. The phase formation and morphology of Mg2Si before and after spraying was investigated with X-ray diffraction and scanning electron microscopy. The Mg2Si coatings were also characterized for their thermal and electrical conductivities. The results showed that the Mg2Si coatings included Mg2Si as the main phase with impurity phases MgO and Si, and had about half thermal conductivity of the bulk and reasonable electrical conductivity.