Mechanical properties and microstructural evolutions during hot deformation of Co–Cr–Fe alloy

Hot deformation tests were performed under various temperature and strain rate conditions to determine the optimal hot working conditions for the Co–Cr–Fe alloy, extensively used in the aerospace industry for its excellent hardness and high wear resistance. The mechanical properties and microstructure observations showed that the flow stress of the sample, composed of M₇C₃–M₂C carbides and face-centered cubic matrix, increased with decreasing temperature and increasing strain rate. Furthermore, as the deformation temperature increased, the volume fraction of recrystallized grains increased at equivalent strain levels, and the dynamic recrystallization mechanism transitioned from continuous dynamic recrystallization to discontinuous dynamic recrystallization. Based on the activation energy (Q_c = 419.4 kJ/mol) and power exponent (n = 5.2) achieved from the true strain–stress curves, it was concluded that dislocation climb creep was the dominant deformation mechanism during hot working of the Co–Cr–Fe alloy.