Hot Deformation Behavior and Microstructural Evolution of an Fe-Cr-W-Mo-V-C Steel

The hot compression deformation behavior and microstructural evolution of an Fe-Cr-W-Mo-V-C steel have been investigated by hot compression deformation experiments carried out at 900 °C to 1150 °C and under strain rates varying from 10 to 0.1 s−1. The results revealed that the flow stress decreased with decreasing strain rate, while increasing deformation temperature led to a lower flow stress. An Arrhenius-type equation was used to analyze the effects of the strain rate and deformation temperature on the plastic flow behavior of the steel. Based on this equation and the experimental results, the average activation energy was calculated to be 747.7 kJ/mol. The tested samples were subjected to careful microstructural examinations, with a focus on determination of the dynamic recrystallization (DRX) grain sizes. A straightforward contour map correlating the DRX grain sizes with the different deformation conditions was drawn. According to this map and the microstructural examination results, the optimum hot working parameters enabling us to obtain appropriate DRX microstructures have been identified at 0.1 s−1 for the strain rate and 1100 °C for the deformation temperature.