PURPOSE: To produce a hot rolled Si-containing steel plate excellent in hot dip galvanizing suitability and alloying treatability by applying, after acid pickling treatment, spesific skin pass rolling to a hot rolled plate of high Si steel by using a work roll having specific surface condition and specific diameter.
CONSTITUTION: Acid pickling treatment is applied to a hot rolled steel plate containing ≥0.2wt.% Si. Then, skin pass rolling is applied to this hot rolled steel plate at ≤5.0% draft. As to a work roll used for this rolling, the grinding marks of the roll are equally distributed in a roll shaft direction and center line average height Raθ in a roll periphery direction and roll diameter are regulated to 0.1-0.6μm and ≥400mm, respectively, and also average peak-to-peak spacing θw in a roll periphery direction satisfies the condition represented by an inequality. By this method, plating, excellent in adhesion and free from uncoating, can be applied to a base material composed of Si-containing steel plate.
KASEDA YOSHIYUKI
HORI MASAHIKO
