A new trivalent chromium iridescent passivation process for zinc coating is developed through probing test,orthogonal experiment and single-factor test.

High-corrosion resistant trivalent chromium,bright blue passivation solution,iridescent passivation solution and black passivation solution have been developed successfully in our laboratory,and the relationship between various parameters and corrosion resistance and ornamentation was studied.

Study of trivalent chromium iridescent passivation technology producing high corrosion resistance for electroplated zinc coatings;

The mechanism on the appearance of hexavalent chromium in passivation films of trivalent chromium iridescent passivation for zinc coating was suggested,and the influences of various parameters(the passive temperature;pH value;solution concentration;solution ingredient etc.

In this work,we developed a novel trivalent iridescent passivation and studied the influence of various technical parameters on the surface appearance and corrosion resistance of the passivation film.

The causes for the formation of hexavalent chromium in trivalent chromium iridescent passivation film were analyzed in terms of the formulation and temperature of trivalent iridescent passivation bath as well as zinc electroplating process.

LH-8 iridescence treatment agent for aluminum parts;