To provide a cold-rolling and pickling method for making the irregularity of the surface which is generated on the surface of a thin stainless steel strip which is manufactured by a twin drum type continuous sheet casting method invisible.
By rolling the strip with grinding marks having an angle of ≥5° to the rotational direction of a roll, dividing the inhomogenity of structure of the segregated part of components which is the source of the irregularity of the surface into sections, making it into discontinuous distribution and making pickling conditions more difficult to perform flame scarfing, the reveal of the irregularity of the surface is suppressed. As for the grinding marks imparted to the roll, the mark which is inclined at ≥5° to the rotational direction of the roll is used and rolling of at least one or more passes except the final pass is performed at the draft of ≥5° per pass. As for the grinding marks imparted to the roll, the mark of ≥1 μm by ten point average roughness is employed. A mixed liquid of nitric acid of ≤70 g/l and fluoric acid of ≤30 g/l is used for the pickling liquid and the temperature of the acid liquid is defined as ≤70°C and pickling time as ≤40 s.
UCHIDA HIDE
OGAWA SHIGERU
