Steel sheets for preparing welded and coated cans and method for manufacturing the same

摘要

A steel sheet utilized to prepare cans comprises an iron base sheet, a Fe-Sn alloy layer formed on the iron base sheet and containing 0.05-0.7 g/m2 of tin and 40-80 atomic % of iron, and a composite oxide film formed on the alloy layer and containing Fe, Sn, Cr and O. The composite oxide film is formed by applying a cathodic dichromate treatment to the steel sheet which has been quenched and cooled to form an oxide film on the alloy layer, the oxide film containing both of tin and iron oxides being converted to the composite oxide film.