Fracture toughness and fracture micromechanism in a cast AlCoCrCuFeNi high entropy alloy system

Abstract This investigation is aimed to understand crack initiation resistance and mechanism of cracking in a high entropy alloy, Al 23 Co 15 Cr 23 Cu 8 Fe 15 Ni 15 (at%). The fracture toughness of the alloy consisting of primarily Fe–Cr rich disordered and Al–Ni rich ordered BCC phases is found to be 5.4±0.2 MPa m 1/2 . Lower magnitude of fracture toughness has been attributed to nanosized microstructural constituents, in which cracking is governed by formation of shear bands, cleavage facets and herringbone type features.

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