Microstructure and Mechanical Properties of Nanocrystalline AlCrFeMnNiWx (x = 0, 0.05, 0.1, 0.5) High-Entropy Alloys Prepared by Powder Metallurgy Route

The present work explores the synthesis of nanocrystalline tungsten-containing AlCrFeMnNiWx (x= 0, 0.05, 0.1, 0.5 mol) high-entropy alloys (HEAs) by mechanical alloying with subsequent Spark Plasma Sintering (SPS) route. Microstructure, thermal stability, and mechanical properties of designed HEAs are critically analyzed and discussed. It is found that nanocrystalline HEA powders exhibit the presence of primary BCC solid solution phase, and the sintered HEAs at 900 °C show the formation of sigma rich tetragonal phase, ordered B2, BCC phase, and minor FCC solid solution phase. The designed HEAs exhibit excellent hardness (8.31-13.57 GPa) as well as high elastic modulus (165.52-202.3 GPa), which are strongly dependent upon the tungsten content.