Partition of plastic work into heat and stored cold work in CoCrNi-based chemically complex alloys

Abstract

The Taylor–Quinney coefficient (TQC) stands as a critical parameter intricately linked to the thermomechanical coupling plastic deformation behavior, defined as the ratio of heat generation to plastic work. Combining experimental studies and atomistic simulations, the TQC is discussed in the context of three CoCrNi-based chemically complex medium/high-entropy alloys (CoCrNi, CoCrNiFe, and CoCrNiFeMn). Notably, the obtained TQC of these alloys hovers around 0.7, well below the generally assumed value of 0.9–1 in traditional metals associated with adiabatic shearing. The lower TQC implies that these alloys possess the much better capability of storing energy of cold-work. It is further found that immobile dislocations are the most effective carriers for storing the energy of cold-work. Among these three alloys, CoCrNiFeMn exhibits the highest TQC due to its relatively lower density of immobile dislocations and Lomer–Cottrell locks.