High-Temperature Mechanical and Thermoelectric Properties of p-Type Bi^sub 0.5^Sb^sub 1.5^Te^sub 3^ Commercial Zone Melting Ingots

Issue Title: International Conference on Thermoelectrics 2013. Guest Editors: Jihui Yang, Hiroaki Anno, Matt Beekman, Ryoji Funahashi, Yuri Grin, Emmanuel Guilmeau, Jan Koenig, Bertrand Lenoir, Don Morelli, Lasse Rosendahl, James R. Salvador, Jeff Sharp, David Singh, Tsunehiro Takeuchi, Xiegeng Tang, Chunlei Wang, Hsin Wang, Wenqing Zhang, and Tie-Jun Zhu Bismuth telluride-based compounds have been extensively utilized for commercial application. However, thermoelectric materials must suffer numerous mechanical vibrations and thermal stresses while in service, making it equally important to discuss the mechanical properties, especially at high temperature. In this study, the compressive and bending strengths of Bi^sub 0.5^Sb^sub 1.5^Te^sub 3^ commercial zone melting (ZM) ingots were investigated at 25, 100, and 200 °C, respectively. Due to the obvious anisotropy of materials prepared by ZM method, the effect of anisotropy on the strengths was also explored. Two-parameter Weibull distribution was employed to fit a series of values acquired by a universal testing machine. And digital speckle photography was applied to record the strain field evolution, providing visual observation of surface strain. The compressive and bending strengths along ZM direction were approximately three times as large as those perpendicular to the ZM direction independent of the temperature, indicating a weak van der Waals bond along the c axis.[PUBLICATION ABSTRACT]