METHOD FOR TREATING ALUMINUM CONTAINING SURFACES

摘要

A primary film of Ni, Fe, and/or Co is formed on an aluminum surface and a phosphate film is formed on the aluminum surface on which this primary film has been formed, or on a composite of an aluminum surface on which a primary film has been formed and a zinc based coated steel sheet. This method of surface treatment is not accompanied with pollution problems with Cr<6+> ion and F<->, and there is little deterioration of the phosphate film forming treatment liquid with use.