Effects of Annealing Treatment on Microstructure and Thermoelectric Properties of Ba8Al16Si30
Clathrate Ba8Al16Si30 was produced by arc melting and annealing effects on the microstructure and thermoelectric properties were investigated. The phase transformation behavior of arc-melted Ba8Al16Si30 was examined by thermogravimetric analysis, differential scanning calorimetry, hardness test, X-ray diffraction and scanning electron microscope analyses. Isothermal annealing was carried out to induce the transformation to a thermoelectric phase at 500°C to 700°C for 5 hrs. Thermoelectric properties in the temperature range between 300K and 600K were measured and evaluated. Electrical conductivity was decreased and Seebeck coefficient was increased with increasing isothermal annealing temperature. The arc-melted and the isothermal annealed specimens represented n-type conduction at temperatures examined, and they showed reliable thermoelectric behaviors.
Jang Hyun Sung, Chan Gyu Lee, Yong Zoo You, Young Kook Lee and Jae Young Kim
J. I. Lee et al., "Effects of Annealing Treatment on Microstructure and Thermoelectric Properties of Ba8Al16Si30 ", Solid State Phenomena, Vol. 118, pp. 561-564, 2006