A lightweight NbMoZrTi refractory high entropy alloy with high specific strength

Refractory high entropy alloys are an obstacle to their use as engineering applications due to their low room temperature ductility and high density. In the present work, a new low-density Nb-Mo-Zr-Ti RHEA was prepared by vacuum arc melting method. The as-cast alloy exhibits a single BCC phase with lower density and higher hardness of 7.4331 g/cm3 and 522 HV. The compressive yield strength of 1462 MPa at room temperature, peak strength of 2158 MPa, and strain at break of 24.6 %. The specific yield strength of this alloy is the highest among all other reported RHEAs, and the ultra-high specific yield strength and excellent strong plastic synergistic effect provide important experience in designing and preparing lightweight structural materials for practical applications.