Mechanical Properties and Phase Stability of WTaMoNbTi Refractory High-Entropy Alloy at Elevated Temperatures

• DOI: 10.1007/s40195-021-01263-9
• Publication Date: 2021-06-25T17:02:56Z
• Authors: Yixing Wan; Jinyong Mo; Xin Wang; Zhibin Zhang; Baolong Shen; Xiubing Liang
• Keywords: Equiaxed crystals; Atmospheric temperature range; Elongation

High-temperature structural metals remain in high demand for aerospace aircraft, gas turbine engines, and nuclear power plants. Refractory high-entropy alloys (RHEAs) with superior mechanical properties at elevated temperatures are promising candidates for high-temperature structural materials. In this work, a WTaMoNbTi RHEA with adequate room temperature plasticity and considerable strength at 1600 °C was fabricated by vacuum arc-melting. The room temperature fracture strain of the as-cast WTaMoNbTi RHEA was 7.8%, which was about 5.2 times that of the NbMoTaW alloy. The alloy exhibited a strong resistance to high-temperature softening, with a high yield strength of 173 MPa and compressive strength of 218 MPa at 1600 °C. The WTaMoNbTi RHEA possessed excellent phase stability in the range of room temperature to 2000 °C. The dendritic grains grew into equiaxed grains after compression test at 1600 °C due to the dynamic recrystallization process at high temperature. This work presents a promising high-temperature structural material that can be applied at 1600 °C.