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

This investigation is aimed to understand crack initiation resistance and mechanism of cracking in a high entropy alloy, Al23Co15Cr23Cu8Fe15Ni15 (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. (C) 2014 Elsevier B.V. All rights reserved.