The effect of Ti on the sintering and mechanical properties of refractory high-entropy alloy TixWTaVCr fabricated via spark plasma sintering for fusion plasma-facing materials

Abstract

The synthesis and characterization of TixWTaVCr alloys for high-temperature and fusion plasma-facing applications are presented in this study. Specimens of TixWTaVCr containing 0 to 7 at% Ti were prepared via spark plasma sintering of an elemental powder mixture at 1500 °C. Characterization of sintered samples via X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy revealed increased formation of a BCC solid solution due to the addition of up to 7 at% Ti. Mechanical characterizations of the TixWTaVCr alloys indicate that they are harder and stronger than several reported high-entropy alloys. The alloy that contained 7 at% Ti also exhibited improved oxidation resistance in air at 1000 °C. Its improved strength, hardness, and oxidation resistance suggest future applications for this high-entropy alloy in high-temperature and nuclear applications.