Abstract
There is considerable interest in thermoelectric generators for a variety of applications, including the conversion of waste energy into electricity. LAST (Lead-Antimony-Silver-Tellurium) has a ZT (dimensionless figure of merit) of 1.7 at 700 K, which implies potential application of LAST materials in the fabrication of thermoelectric generators with relatively high efficiency at high temperatures. Porosity is important when looking at thermoelectric materials as porosity in brittle materials affects a range of electrical, thermal, and mechanical properties. Using the non-destructive method of resonant ultrasound spectroscopy (RUS), the effect of porosity on the room temperature Young's modulus, shear modulus, and Poisson's Ratio are investigated for two LAST compositions (Ag0.43Pb18Sb1.2Te20 and Ag0.86Pb19Sb1.0Te20) and two fabrication processes (casting and hot pressing).
