Notch shape dependence of fatigue crack extension in equiatomic CrMnFeCoNi high-entropy alloy

Abstract Fatigue tests were conducted on an equiatomic CrMnFeCoNi high-entropy alloy with three different micro-stress concentration sources. A fatigue crack behavior analysis using a replica of a specimen surface, fractographic analysis in a fracture surface, fatigue crack shape analysis, and strain analysis under the fracture surface were performed. It was found that the fatigue crack extension mode was transited by the severity of the strain concentration from the damage accumulation mode to the plastic deformation mode.