Influence of a Cold Plastic Deformation on the Electrical Resistivity of CrMnFeCoNi High-Entropy Alloy

The influence of a cold rolling deformation on the electrical transport properties of CrMnFe-CoNi high-entropy alloy (HEA) has been studied. It is shown that the growth of the strain.. at rolling gives rise to a decrease of the alloy electrical resistivity rho and an increase of the temperature coefficient of resistance alpha. The X-ray diffraction study did not reveal any phase changes at that. Such dependences of rho and alpha on epsilon differ from the behavior of those parameters in the majority of ordinary metal alloys. The temperature dependence of the electrical resistance of deformed samples at their heating is found to have an abnormal S-like shape. Using the positions of such S-anomalies obtained at different heating rates, the activation energy E-a of the process responsible for the appearance of this anomaly is determined with the help of the Kissinger method. The form of the dependence rho(T) and the value of E-a give us ground to connect the specific features in the behavior of rho in deformed specimens with the existence of a "K-state" in the examined HEA, which emerges in some deformed alloys based on transition metals. Possible thermodynamic reasons for the appearance of this state have been discussed.