Grain Orientation And Precipitation Behavior Of Inhibitors In Hot Rolled Strip Of Hi-B Steel Produced By CSP Process

Manufacturing high magnetic induction grain-oriented electrical steel(Hi-B steel)produced by compact strip production(CSP)process is the primary emphasis on research in industry,currently,due to its short production cycle,low energy consumption and simple processing method.For the present casting slab and hot rolled strip of Hi-B steel produced by CSP process,the microstructure,textures and the size,distribution and species of inhibitors were studied by microscope,EBSD and TEM techniques;the evolution of the grain orientation and the behavior of inhibitors were analyzed in hot rolling process;A nucleation model of the secondary phase taking MnS as an example was proposed based on classical nucleation theory.The research of this paper has a certain theoretical support and significance for producing Hi-B steel by CSP process.The texture intensity of hot rolled strip produced by CSP process was higher than that produced by traditional process,there ware mainly {110} plane texture and a small amount of exact Goss grains were observed in the surface layer,and few brass texture components and copper texture components were distributed.The exact Goss grains were adjacent to the brass and copper grains.A amount of small particles containing copper were observed in casting slab and hot rolled strip for cooling to room temperature,these particles could act as inhibitors.And particles containing copper,aluminum,manganese can hardly act as particles for their large size.A modified nucleation model of the secondary phase of Hi-B steel produced by CSP process was proposed combining with the features of CSP process based on classical nucleation theory.The more accurate calculation method of relative nucleation rate and the more accurate Nr T curve and PTT curve were obtained by considering more accurate site density of precipitation.The precipitate simulation of MnS showed the dislocation nucleation was the main nucleation mechanism,the temperature of the largest nucleation rate of MnS precipitate was 750?;MnS precipitated fastest in dislocation when the temperature was 800? and precipitated fastest homogeneously when the temperature was 750?.The largest precipitation density of MnS can be obtained if the roll temperature was at 750~800? by controlling the hot rolling stage of CSP process.