Elemental segregation in CoCrFeMnNi high entropy alloy after intermediate-temperature low cycle fatigue loading

We report on the elemental segregation in CoCrFeMnNi high entropy alloy after low cycle fatigue loading at 550 °C via transmission electron microscopy. The segregation of Fe, Co and Ni elements at the grain boundaries was identified, which is in addition to previously reported precipitation of MnNi-rich and Cr-rich phases. Besides, cyclic straining is suggested to play an assisting role in the precipitation of these phases and the elemental segregation upon cycling CoCrFeMnNi at intermediate temperatures. In addition, various dislocation patterns in the post-fatigued CoCrFeMnNi are compared to those in monotonic loading.