Ductile Ti1.5ZrNbAl0.3 refractory high entropy alloy with high specific strength.

• A novel high specific strength plastic Ti 1.5 ZrNbAl 0.3 RHEAs was developed. • The tensile specific yield strength of this alloy is up to 145.5 MPa g−1 cm3. • The tensile fracture elongation of this alloy is up to 23.0%. • The specific yield strength-plasticity synergy is the best among all other RHEAs. • Short-rang orderings and cross-slip generate the strength-plasticity synergy. The ambient temperature brittleness and high density of refractory high entropy alloys (RHEAs) are the obstacles for their applications as structural materials. A novel ductile body-centered cubic Ti 1.5 ZrNbAl 0.3 RHEA with high specific strength was developed. The tensile specific yield strength and fracture elongation of this alloy are 145.5 MPa · g−1 · cm3 and 23.0%, respectively. The specific yield strength is the highest among all other reported RHEAs. The superior mechanical properties of the Ti 1.5 ZrNbAl 0.3 RHEA arise from the solid solution strength and cross-slip of dislocations. The ultrahigh specific yield strength and superior strength-plasticity synergy may promote the applications of RHEAs. [ABSTRACT FROM AUTHOR]