Structure and Properties of Melt-Quenched Al4CoCrCuFeNi High-Entropy Alloy

Abstract

The structure and mechanical properties of a multicomponent high-entropy Al4CoCrCuFeNi alloy in the as-cast and melt-quenched states were investigated. The alloy composition was analyzed based on the literature criteria for predicting the phase formation in high-entropy alloys, which considered the entropy and enthalpy of mixing, valence electron concentration as well as the atomic size difference of the components. The alloy films were synthesized by quenching from the melt using a splat-quenching technique. The cooling rate of the films was estimated to be ~ 106 K/s based on the film thickness. The X-ray diffraction analysis revealed that both as-cast and melt-quenched Al4CoCrCuFeNi alloy samples had an ordered B2 phase in their structure. The microhardness of the as-cast alloy was 6500 MPa, while the microhardness of the melt-quenched film was significantly higher and reached 9400 MPa.