摘要 |
A process of hot-dip coating a strip of cold rolled low carbon steel having as an essential alloying element at least one strong oxide forming metal, such as titanium, aluminum, silicon or chromium or a combination thereof, to overcome the difficulty of uniformly hot-dip coating such steels with aluminum and other protective metals on a Sendzimir-type hot-dip coating line wherein the steel strip is thoroughly cleaned by washing in an alkaline cleaning solution, brushing and drying to remove metallic particles and non-metallic contaminants, forming a dry film coating on a clean dry surface of the strip of a higher fatty acid amide having from 8 to 18 carbon atoms, heating said strip to a temperature sufficient to completely volatilize said amide film coating, passing said strip through a heating zone containing a reducing atmosphere in which the strip is heated to a temperature of at least about 704 DEG C. (1300 DEG F.), cooling said strip in a reducing atmosphere to about the temperature of a molten aluminum hot-dip coating bath, and passing said strip through said hot-dip coating bath. The amide coated steel strip has excellent corrosion resistance when stored in coiled form and is adapted for uniform hot-dip coating with aluminum on a Sendzimir-type hot-dip coating line.
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