Microstructure-driven property enhancement of CoCrFeNiAl 0.5 high-entropy alloy via DC fast hot-pressed sintering

The CoCrFeNiAl 0.5 high-entropy alloy (HEA) offers excellent properties for aerospace and energy applications, but conventional processing methods face high costs and low efficiency. Direct Current Fast Hot-Pressed Sintering (DC-FHPS), an innovative and rapid powder metallurgy technique, was used to prepare this alloy. The effect of sintering temperature on microstructure, densification, mechanical properties, and corrosion resistance was investigated. HEAs sintered at 950–1000 °C exhibited FCC + BCC dual phases. Higher sintering temperatures transformed the BCC morphology from rod-shaped to ellipsoidal, reduced Gibbs free energy, and improved interfacial bonding. Densification increased with temperature, reaching approximately 99.96% at 1000 °C, and hardness reached approximately 433 HV. The specimen consolidated at 1000 °C showed superior wear resistance and enhanced corrosion resistance. This study establishes a key theoretical foundation for the industrial rapid manufacturing and engineering applications of CoCrFeNiAl 0.5 HEA, demonstrating DC-FHPS as a cost-effective, efficient powder metallurgy route for advanced materials.