High‐Strength AlCrFeCoNi High Entropy Alloys Fabricated by Using Metallic Glass Powder as Precursor

The report on the formation of high‐strength AlCrFeCoNi HEAs fabricated by using metallic glass powder as precursor is presented. XRD and SEM analysis indicate that the fabricated HEAs have a two‐phase microstructure of a micron‐sized BCC solid solution matrix surrounding a dispersed micron‐sized BCC region. TEM observation reveals that the two‐phase region is all composed of two kinds of nano/ultrafine‐grained BCC grains with respective composition distributions of the Al, Ni rich and Cr, Fe deplete, and the Cr, Fe rich and Al, Ni deplete. Moreover, the fabricated HEAs exhibit simultaneous ultra‐high fracture strength and large ductility, far superior to the cast counterpart HEAs. The results provide a promising method for fabricating large‐sized HEAs with excellent mechanical properties by powder metallurgy.