Room temperature Young's modulus, shear modulus, and Poisson's ratio of Ce_0.9Fe_3.5Co_0.5Sb₁₂ and Co_0.95Pd_0.05Te_0.05Sb₃ skutterudite materials

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• 作者：Robert D. Schmidt ; Jennifer E. Ni ; Eldon D. Case ; Jeffery S. Sakamoto ; Daniel C. Kleinow ; Bradley L. Wing ; Ryan C. Stewart ; Edward J. Timm
• 关键词：Thermoelectric materials ; Elasticity ; Ultrasonics ; Microstructure ; Nanoindentation
• 刊名：Journal of Alloys and Compounds
• 出版年：2010
• 出版时间：20 August 2010
• 年：2010
• 卷：504
• 期：2
• 页码：303-309
• 全文大小：517 K

文摘

Room temperature Young's modulus, shear modulus and Poisson's ratio were measured by Resonant Ultrasound Spectroscopy (RUS) for a total of 29 skutterudite specimens cut from four hot pressed billets: (i) two p-type (Ce_0.9Fe_3.5Co_0.5Sb₁₂) billets, (ii) one n-type (Co_0.95Pd_0.05Te_0.05Sb₃) billet with 0.1 atomic % Ce addition and (iii) one n-type billet without Ce addition. Within a given hot pressed billet, the elastic moduli were very uniform from specimen to specimen. Also, Ce-doping of the n-type specimens did not result in a significant shift in the elastic modulus. For n-type specimens with 98 % relative density, the mean Young's modulus, shear modulus and Poisson's ratio were 140.6 ± 0.2 GPa, 57.34 ± 0.05 and 0.226 ± 0.001 GPa, respectively. For the p-type specimens of similar relative density, the mean Young's and shear moduli were approximately 7 % lower than the n-type, while there was no significant difference between the mean Poisson's ratio values of the n-type and p-type 98 % dense specimens. The measured elastic moduli agreed relatively well with the literature values for other Sb-based skutterudite compositions. In addition, nanoindentation measurements on three mutually orthogonal specimen faces showed no appreciable anisotropy in Young's modulus.