| Mg2Si has long been recognized as one of the promising thermoelectric materials; the fabrication methods are hot press, spark plasma sintering, high temperature sintering, etc. however, application of thermoelectric materials requires large scale manufacturing but traditional manufacturing process cannot reach this goal by its nature; thus we employed thermal spray technology to fabricate such thermoelectric material. In collaboration with Thermal Spray Center in Stony Brook University, we manufactured Mg 2Si coatings on titanium substrate by plasma thermal spray technology. Samples were further characterized in various methods: scanning electron microscopy (SEM) exhibits the micro structures of sprayed Mg2Si coatings; X-ray spectroscopy (XRD) analysis examined the content and various thermoelectric properties by electrical conductivity measurement, thermal conductivity measurement, Seebeck Effect measurement and Hall Effect measurement. The result showed that vacuum plasma thermal spray so far has better thermoelectric properties than atmospheric plasma spray and Mg2Si has potential to increase its thermoelectric properties if proper fabrication environment and post-fabrication processes are employed. |
