Processing and Seebeck Effect Measurement of a Bismuth Based Alloy

The objective of this work is to develop a casting manufacturing process to produce a bismuth-based porous material. Induction heating was applied to melt Bi-Sn alloy in a quartz tube and the molten alloy was cast into loosely compacted sodium chloride powder. After the sodium chloride powder was dissolved by water, pores were generated in the Bi-Sn alloy. The true porosity of the alloy can be controlled as high as 58.7% in volume. The thermoelectric property of the material has been studied to explore the application of this material for energy conversion. The experimental results show that the Seebeck coefficient of the porous bismuth material is independent of porosity. The porosity of the material can be controlled through manufacturing parameters. The higher the porosity is, the slower the heat conduction in the material.