Effect of Ti content on microstructure and properties of TixZrVNb refractory high-entropy alloys

This study aimed to investigate the microstructure and mechanical properties of Ti x ZrVNb ( x = 1, 1.5, 2) refractory high-entropy alloys at room and elevated temperatures. The TiZrVNb alloy consisted of the body-centered cubic (bcc) matrix with a small amount of V 2 Zr phase. The Ti 1.5 ZrVNb and Ti 2 ZrVNb alloys exhibited a single-phase bcc structure. At room temperature, the tensile ductility of the as-cast alloys increased from 3.5% to 12.3% with the increase in the Ti content. The Ti x ZrVNb alloys exhibited high yield strength at 600°C, and the ultimate yield strength was more than 900 MPa. Softening occurred at 800°C, but the ultimate yield strength could still exceed 200 MPa. Moreover, the Ti x ZrVNb alloys displayed low densities but high specific yield strengths (SYSs). The lowest density of Ti x ZrVNb alloys was only 6.12 g/cm 3 , but the SYS could reach about 180 MPa·cm 3 ·g −1 , which is better than those of most reported high-entropy alloys (HEAs).