| 摘要 |
PURPOSE:To prevent blister from generating during plating by adding a limited amount of Al to a molten zinc plating bath. CONSTITUTION:After a hot-rolled steel plate is pickled, the surface thereof is subjected to reducing treatment within a hydrogen gas atmosphere. Subsequently, the treated steel plate is passed through a zinc plating bath to which Al is added so as to satisfy formula 0.20%<= available Al concentration <=0.25%. By this proper addition of Al, the reaction of Zn and Fe within a plating bath is promoted and a residual iron oxide film is removed together with dissolution of Fe into a molten Zn. Therefore, the generation of blister is effectively prevented. |
