Effects of Electric Field Annealing on Recrystallization Texture and Plastic Strain Ratio (r Value) of IF Steel Sheet

摘要

Effects of electric field annealing on recrystallization texture and average plastic strain ratio (r value) of IF steel sheet were studied by mean of X ray diffraction ODF analysis and the tensile test. Specimens of 75% cold-rolled IF steel sheet were annealed at 850℃ for 25min,with and without electric field annealing respectively. Results show that the electric field annealing does not change the type of recrystallization texture and its formation mechanism in IF deep-drawing steel sheet, but improves the formation and development of recrystallization γ-fiber texture, enhances the intensity of γ-fiber texture, and retards the formation and development of α-fiber texture. Comparing with the conventional annealing, electric field annealing improves the average plastic strain ratio (r value). Possible reasons for the intensification of recrystallization γ-fiber texture with the electric field applied may attribute to the reduction of stored energy, thus hindering the formation of other orientated nuclei and enhancing the nucleating ratio of γ-oriented nuclei. And the intensification of recrystallization γ-fiber texture was considered as the main reason for the enhancement of the plastic strain ratio (r value) in IF steel sheet.