Preparation and Performance of Ceramic Coating on Cold-Rolled Steel Sheet

Ceramic coating was prepared on the surface of cold-rolled steel sheets by treatment in aqueous solution of fluorozirconate.The morphology and elemental composition of the ceramic coating were investigated by means of scanning electron microscopy and energy dispersive spectrometry.The corrosion resistance of the ceramic coating was evaluated by conducting electrochemical corrosion test and salt spray test.Besides,the adhesion of the ceramic coating was evaluated,and its film-formation mechanism was analyzed.Results show that as-prepared ceramic coating is extremely thin and mainly composed of the oxides of Fe and Zr,and its color changes with varying film-formation time.The cold-rolled steel treated with the aqueous solution of fluorozirconate had better corrosion resistance than the untreated one,but film-formation time had little effect on the corrosion resistance of the ceramic coating.Moreover,the ceramic coating had a zero degree of adhesion to epoxy resin paint and polyurethane paint,meeting with the requirements for follow-up coating.