A lightweight TiZrV_0.5Nb_0.3Al_0.2 refractory high-entropy alloys with enhanced strength and ductility at low and high strains loading

This study has developed a novel TiZrV_0.5Nb_0.3Al_0.2 alloy, a lightweight refractory high-entropy alloys (RHEAs) with an optimized balance of strength and ductility, suitable for advanced structural applications. This alloy, with a density of ∼5.7 g/cm³, exhibited a single body-centered cubic structure with locally compositional fluctuations, extensive solid solution strengthening, and active multiple slip systems. Rigorous testing of this alloy revealed a tensile yield stress (YS) of 1048 ± 10 MPa, an elongation of 32 ± 3 %, and a specific YS of 184 ± 2 MPa g⁻¹ cm³ at a strain rate of 0.001 s⁻¹, surpassing traditional lightweight alloys. Under dynamic loading conditions (2500-5000 s⁻¹), this alloy possessed the YS of 1800∼2500 MPa, demonstrating high resistance to adiabatic shear failure. Such exceptional mechanical properties highlight the great potential for RHEAs as next-generation lightweight structural alloys.