Ferritic stainless steel sheet with a low a planar anisotropy and with excellent resistance to formation of grooves; a method for its production

摘要

A ferritic stainless steel sheet having less planar anisotropy and excellent anti-ridging characteristics is disclosed. The sheet includes not more than about 0.02 wt % of C, about 0.01-1.0 wt % of Si, about 0. 01-1.0 wt % of Mn, not more than about 0.08 wt % of P, not more than about 0.01 wt % of S, about 0.005-0.30 wt % of Al, about 11-50 wt % of Cr, about 0.1-5.0 wt % of Mo, not more than about 0.03 wt % N, with the contents of C and N satisfying the relations: about 0.005 wt %≦(C+ N) about 0.03 wt %, and (C/N) about 0.6. The sheet also includes Ti in an amount to satisfy the relation: about 5≦Ti/(C+N). ltoreq. about 30. The balance of the sheet includes Fe and incidental impurities, with the sheet having an X-ray integral intensity ratio (222) /(310) of not less than about 35 in a plane parallel to a sheet surface at a depth of 1/4 of the sheet thickness from the sheet surface. This ferritic stainless steel sheet may be produced by a method which includes hot rolling said steel having the above-described composition at a final pass reduction ratio during rough rolling of not less than about 40% and at a final finish rolling temperature of not more than about 750° C. The hot rolled sheet is subsequently annealed, cold rolled, and finish annealed.