Synergistic strengthening of a TiZrNiAlCu high-entropy alloy by phase transformation and nanophase precipitation under ultrahigh pressure

Ultrahigh-pressure solidification is a solidification technique carried out in a high-pressure environment. It can significantly change the solidification behavior, thus affecting their mechanical properties. On this basis, this work aims to explore the feasibility of modulating the strength of TiZrNiAlCu high-entropy alloys via the ultrahigh-pressure method. The transformation of the BCC phase into the HCP phase and nanoprecipitated phase is the key to optimizing the mechanical properties under the 7 GPa high-pressure solidification condition; the hardness of the matrix W phase (TiZr-rich) increases by 16 % from 7.46 to 8.676 GPa, the yield strength increases by 19 % from 1.184 to 1.418 GPa, and the hardness of the B phase (NiAl-rich) increases by 19 % from 7.621 to 8.466 GPa. GPa to 8.466 GPa, an increase of 11 %, and the yield strength increases from 1.212 GPa to 1.378 GPa, an increase of 13 %. This work provides a new direction for microstructure based strengthening of high-entropy alloys.