Study on the influence of Hf, Zr and Mo elements on the mechanical properties of equimolar TiVNbTa refractory high-entropy alloy

Abstract

The addition of alloying elements would improve the properties of refractory high-entropy alloys at room temperature and high temperatures. Hf, Zr and Mo elements were added in TiVNbTa refractory high-entropy alloys. Mechanical properties and microstructures after deformation were studied through compressive and tensile tests and microstructural characterization. Hf, Zr and Mo elements would increase the ambient strength of TiVNbTa alloy owing to increased atomic size difference and shearing modulus difference. However, Zr and Mo would deteriorate the ambient ductility, and Hf and Zr would decrease the high-temperature strength owing to lower shearing modulus and melting points. Moreover, the Zr-enriched BCC phase would precipitate after compression at 1000°C.