Effect of texture on r-value of ferritic stainless steel sheets

Abstract

The effects of cold rolling texture on the formation of recrystallization texture and the relationship between recrystallization texture and r-value were investigated for sheets of titanium-stabilized extra-high purity Type 436L and Type 409L ferritic stainless steels. The recrystallization texture and average r-value were affected by the cold rolling texture. Annealed sheets with a sharp γ-fiber texture and very high average r-values were obtained from cold-rolled sheets with a strong γ-fiber texture (Type A). On the other hand, the {h,1,1}<1/h,1,2> fiber texture developed from cold-rolled sheets with a strong a -fiber texture (Type C). In terms of the relationship between {111} intensity and the average r-value, chromium content had less effect than the cold rolling texture. The planar anisotropies of r-values and the average r-values of Type 436L and 409L sheets with Type A cold rolling textures agreed well with those calculated from the textures in the center layers by using the relaxed-constraints model and the CRSS ratio τc{211}/ τc{110} of 1.1. On the other hand, for the sheets with Type C cold rolling textures and a marked texture gradient, it was necessary to consider the texture gradient in the thickness direction. The texture inhomogeneity by the orientations other than {111} texture affected the relationship between {111} intensity and average rvalue. © 2011 ISIJ.