Influence of vanadium content on AlCuZrV medium-entropy alloy: mechanical properties and high-temperature stability

Due to their exceptional mechanical properties, high–temperature stability, and corrosion resistance, medium-entropy alloys (MEAs) have emerged as promising candidates for aerospace, energy, and automotive manufacturing industries. In this paper, we investigate the effect of varying vanadium content on the strength, high-temperature stability, and oxidation resistance of AlCuZrV MEAs. Using the vacuum arc melting method, a series of AlCuZrV medium-entropy alloys (MEAs) with varying vanadium contents were prepared, and their compositions were analyzed. The compressive strengths of these alloys were evaluated using the INSTRON 5985 universal testing machine. The results revealed that the compressive strength of the alloys is significantly enhanced by increasing the vanadium content, with the precipitation of vanadium–rich phases contributing to enhanced mechanical properties. Fracture surface analysis showed that AlCuZrV medium–entropy alloys exhibited mirror–like, rough–like, and crumb–like morphologies as vanadium content increased. The crack propagation mode also changed from linear propagation to branching, which is related to solid solution and second-phase strengthening. Furthermore, the oxidation starting temperature of high-strength AlCuZrV2 can reach 500 °C, which is about 300 °C higher than the onset temperature of commercial aluminum alloys (∼200 °C). The findings of this study offer valuable insights into tailoring the mechanical properties and high-temperature stability of medium-entropy alloys through microstructural engineering.