Abstract
A precoated steel sheet without dissolvable Cr(VI) for automotive fuel tank use has been developed. The newly developed Cr(VI)-free precoated steel sheet consists of thin organic resin coatings on an electrogalvanized steel sheet. One side of the sheet is coated by a 1μm thick lubricant resin layer used for the outside of the tank. The other side is coated by a 3μm thick gasoline resistance resin layer which contains metallic powders to provide good weldability. Cr(VI)-free precoated steel sheet showed good internal and external corrosion resistance, weldability, press formability in comparison with Pb-8%Sn alloy coated steel sheet.
