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arXiv · 2204.07993

Elastic properties of a Sc-Zr-Nb-Ta-Rh-Pd high-entropy alloy superconductor

Yupeng Pan·Xiaobo He·Binjie Zhou·Denver Strong·Jian Zhang·Hai-Bin Yu·Yunfei Tan·Robert J. Cava·Yongkang Luo
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Abstract

We report a comprehensive study on the elastic properties of a hexanary high-entropy alloy superconductor (ScZrNbTa)$_{0.685}$[RhPd]$_{0.315}$ at room and cryogenic temperatures, by Resonant Ultrasound Spectroscopy experiments. The derived elastic constants are bulk modulus $K=132.7$ GPa, Young's modulus $E=121.0$ GPa, shear modulus $G=44.9$ GPa, and Poisson's ratio $\nu$=0.348 for room temperature. The Young's and shear moduli are $\sim 10\%$ larger than those in NbTi superconductor with similar $T_c$, while the ductility is comparable. Moreover, the mechanical performance is further enhanced at cryogenic temperature. Our work confirms the advantageous mechanical properties of high-entropy alloy superconductors and suggests the application prospects.

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cond-mat.supr-concond-mat.dis-nncond-mat.mtrl-scicond-mat.othercond-mat.str-el

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Yupeng Pan, Xiaobo He, Binjie Zhou, Denver Strong, Jian Zhang, Hai-Bin Yu, Yunfei Tan, Robert J. Cava, Yongkang Luo. 2022-04-17. Elastic properties of a Sc-Zr-Nb-Ta-Rh-Pd high-entropy alloy superconductor. https://doi.org/10.1016/j.mtcomm.2022.104265

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