Effect of boron on planar anisotropy of r-value in extra-low-C IF steel sheet

The planar anisotropy, of r-talue was investigated of extra-low-C,Ti and Nb added interstitial-atom free (IF) steels with various B contents. The anisotropy of r-value is preferably decreased by addition of B, although mean r-value Itself after cold rolling and recrystallization treat ment is slightly lowered. Addition of B does not affect the grain size of hot band leading to small influence on r-value in cold-rolled and annealed sheet, In the texture of the: hot band, strong gamma- and alpha-fibres, especially, {001}< 110 >, {332}< 113 >, {113}< 110 > are formed by B addition. On the other hand no specific sharp orientation is obtained in B-fret: steel, BS cold rolling and recrystallisation. these hot rolling orientations are rotated toward stable orientations. It is estimated that these hot rolling orientation in ultra-low-C IF B-bearing steel decrease the planar anisotropy of r-value after the cold rolling and recrystallization treatments.