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

TL;DR

This study characterizes the elastic properties of a high-entropy alloy superconductor using ultrasound spectroscopy, revealing superior mechanical performance at cryogenic temperatures compared to traditional superconductors.

Contribution

It provides the first comprehensive elastic property measurements of a hexanary high-entropy alloy superconductor at various temperatures.

Findings

Young's and shear moduli are ~10% larger than NbTi superconductor.

Mechanical performance improves at cryogenic temperatures.

Elastic constants indicate good ductility and mechanical robustness.

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.