To obtain a stainless steel sheet excellent in surface characteristic by applying reduction to a cast slab prior to cold-rolling of a continuously cast thin cast slab and cold-rolling after adjusting γ grain diameter by annealing at a specified temp.
Prior to cold rolling, cold rolling with a draft of 5-15% is applied to this thin cast slab. Thereafter, annealing is applied at 900-1050°C to regulate the γ grain diameter to ≤60 μm. Since the surface of the cast slab is covered with scale due to the annealing, a pickling treatment is applied. The method for the pickling treatment includes pickling with e.g. a mixture of hydrofluoric acid and nitric acid after shot blasting. Cold rolling is then applied to obtain an austenitic stainless steel sheet having ≤20 μm Ra surface roughness and excellent in the surface characteristic. Further, the annealing and the pickling treatments in the conventional method are applied, or a bright annealing is applied instead of annealing and pickling. Ruggedness on the surface of the steel sheet having ≤20 μm Ra surface roughness is evaluated as not visually sensed.
TAJIMA ITARU
SHIRAI YOSHIHISA
