PURPOSE: To improve processability and corrosion resistance, by a method wherein an iron-aluminum alloy layer of an aluminum plated steel sheet is broken partly and a saturated polyester resin coating is applied on a plated coating obtained by performing directly metallic joining of aluminum alloy though a chromium compound coating or a phosphate coating.
CONSTITUTION: A molten aluminum plated steel sheet which is durable for even DI processing is formed by keeping at least 10% joining between metals by breaking an allow layer partly without peeling a plated layer. A cold rolling method is optimum as a method breaking the alloy layer without peeling the plated layer. When a quantity of an alloy layer is little (about 1-4 microns), at least 10% iron-aluminum metallic joining is obtained at a pressing rate of about 5-30%. Either a chromium work is coated through chromate treatment or a phosphate coating is formed as ground treatment of the coating. A chromium phosphate coating of 3-50mg/m2 is formed as chromium. Saturated polyester resin film is laminated to the surface of the steel sheet either through an adhesive agent layer or by making use of thermal adhesion. It is preferable that the thickness is 10-100 microns.
TANIMURA KOJI
BABA TAKASHI
