Effect of Hot-rolling Conditions on Texture and R-value of 16%Cr Ferritic Stainless Steel

Effect of Nb or Ti addition on texture formation and r-value of 16%Cr stainless steels was investigated to clarify the reason for keeping r-value of Nb or Ti free type 430 stainless steel low. Hot rolling conditions were examined to improve r-value and riding property of type 430 stainless steel. {111} texture was developed when Nb or Ti/(C+N) (at%) was over 1.0, and {111} texture was not developed in Nb or Ti free type 430 stainless steel because carbides and nitrides were dissolved before recrystallization during a final annealing. Higher reduction up to 60%/pass in rough hot rolling made r-value and riding propety improved by increasing {111} and decreasing {001} textures in a cold-rolled and annealed type 430 stainless steel, however reduction of 70%/pass lowered r-value. It is supposed a crystal rotation toward {001} occurred during a rough hot rolling, and the {001} texture remained after a hot band annealing, cold rolling and final annealing.