FERRITIC STAINLESS STEEL WITH GOOD FORMABILITY AND THE METHOD OF MANUFACTURING THE SAME

摘要

PURPOSE: A ferritic stainless steel having an excellent formability and a manufacturing method thereof are provided to manufacture a ferritic stainless steel hot annealed plate in which a shear texture develops from the surface layer of the plate to the vicinity of the central layer of the plate. CONSTITUTION: A ferritic stainless steel having an excellent formability is manufactured with a composition in which a maximum austenite fraction defined as a following equation (1) is below 20 wt%. The equation (1) is as follows:γ(%) = 420 * C + 470 * N + 23 * Ni + 9 * Cu + 10 * Mn + 180 - 11.5 * Cr - 11.5 * Si - 12.0 * Mo - 52.0 * Al. The composition satisfies a following equation (2). The equation (2) is as follows: 0.5 <= Mn + Al + 20 * (S + N) <= 40. The fraction of crystal grains having Goss orientations in a micro structure measured from the surface layer of the steel to the quarter point of the entire thickness of the steel is over 25%.