Analyzing the Phase Evolution, Microstructure and Wear Response of Spark Plasma Sintered Al0.5CoCrFeNi2 High Entropy Superalloy

High entropy superalloys (HESA), an extension of high entropy alloys (HEAs), exhibit excellent high‐temperature properties with low density, making them a potential replacement for expensive and heavy superalloys. While multiple processing routes are available for HEAs, spark plasma sintering is becoming increasingly popular due to its ability to fabricate alloy powder in short period of time. Herein, the phase evolution and microstructural development of gas atomized Al0.5CoCrFeNi2 HESA powder fabricated using spark plasma sintering and the wear properties of the sintered specimen are reported. The alloy powder and all the specimen sintered in the range of 800–1050 °C show an extremely stable single‐phase face centered cubic structure. Relative density of 99% is achieved at 1000 °C and above with porosity pinning effect playing an important role in densification behavior and grain growth. In all the sintered specimen, a combination of adhesive, delamination, oxidation, and abrasive wear is observed, with the coefficient of friction lying in the range of 0.6–0.7. Al0.5CoCrFeNi2 high entropy superalloy retains the face centered cubic phase even with sintering temperature as high as 1050 °C. Porosity pinning largely influences the densification of alloy powder during sintering. The hardness and wear of spark‐plasma‐sintered specimens is affected by the percentage porosity and its distribution. Analysis reveals adhesive wear, delamination, and oxidation wear.