| 摘要 |
PURPOSE:To obtain a corrosion resisting steel sheet excellent in aluminizing suitability and adhesive strength of plating by simple operations by means of applying Fe-P alloy plating to a Cr-containing steel sheet by a specific coating weight, applying heating to the above steel sheet in a specific atmosphere, and then immersing the steel sheet into a molten Al bath. CONSTITUTION:Fe-P alloy plating is foregoingly applied to the surface of a steel sheet containing, by weight, >=3% Cr by 0.05-3.0mum coating weight per side. Subsequently, the above steel sheet is heated in a nonoxidizing atmosphere and then immersed into a molten Al or Al-alloy bath to undergo hot-dip aluminizing. If Ni undercoat plating of 0.005-3.0mum coating weight is performed prior to the Fe-P precoating, the adhesive strength between the precoating film on the Ni undercoat plating film and the aluminizing film can be improved. It is desirable to regulate the content of P in the Fe-P alloy plating to 0.05-1.5%, and also it is preferable to use a bath containing about 3-13% Si as the above Al-alloy bath. This plated steel sheet is useful in the fields requiring high corrosion resistance, such as automobile exhaust gas pipe. |
