Influence of Temperature Evolution on Precipitation Behaviour of Second Phase Particles in Grain‐oriented Electrical Steels

Abstract

AbstractA model concerning dynamic precipitation of second phase particles during hot deformation of conventional grain‐oriented electrical steels is proposed. The model involves the solid solubility of the elements forming MnS, the corresponding nucleation driving force, as well as the evolution of dislocation densities during hot deformation, which supplies sites for heterogeneous nucleation of MnS particles. The model describes the dynamic process in which temperature keeps decreasing and dislocation density keeps increasing. The influences of reheating temperature, initial rolling temperature, finishing temperature and deformation duration on the precipitation behaviour are involved. Calculations have been conducted based on the model, to simulate the precipitation behaviour of MnS particles during hot rolling of grain‐orientated electrical steels under different parameters. The results indicate that hot rolling is very important for dispersive precipitation of MnS particles. The increase of particle density is promoted by proper increase of reheating temperature or proper reduction of initial and finishing rolling temperature, in which the driving force and dislocation density are increased. The simulation results agree basically with the experimental observations in hot strip of a grain oriented electrical steel.