Influence of hot working parameters on dynamic recrystallisation of GCr15 bearing steel

摘要

The CA scheme coupled with metallurgical principles has enabled quantitative simulation of microstructural evolution during DRX of GCr15 bearing steel. This model considered the effect of the impurities and carbides on the DRX of the steel, by coupling the modified Kocks-Mecking model and the boundary binning effect. From this simulation, it is clear that hot working parameters play an important role in the microstructural evolution and the stress-strain flow behaviour, which ultimately influence the properties of the materials. The simulated results agree with experimental findings in GCr15 bearing steel. The stress-strain curves present the obvious single peak characteristic. The peak and stable stress increase with increasing temperature or decreasing strain rate. The stable DRX grain size is predicted under different thermomechanical conditions. It is found that finer grain size is easy to be obtained during lower temperature or higher strain rate.