Characterization of Nanocrystalline AlCoCrCuNiFeZn High Entropy Alloy Produced by Mechanical Alloying

Abstract

The equiatomic multicomponent nanocrystalline AlCoCrCuNiFeZn heptanary high entropy alloy (HEA) solid solution was produced by mechanical alloying (MA) and characterized by XRD, SEM, DSC and TGA. The 30 hr. mechanically alloyed AlCoCrCuNiFeZn HEA is mainly composed of BCC solid solution shows better chemical homogeneity with crystallite size of about 15 nm in as milled condition. It retains its nanostructure even at a temperature of 850 °C and it is found to be thermally stable. The 30 hr milled AlCoCrCuNiFeZn heptanary alloy powder was consolidated through hot compaction at a temperature of 850 °C for 2 hr. From Nanoindentation measurements on consolidated samples, hardness and young's modulus values are found to be 7.773 GPa and 152.4 GPa respectively.