Method for nickel-free phosphating metal surfaces

• Main Authors: Schmeier, Lisa, Hollmann, Frank, Dahlenburg, Olaf
• Format: Patent
• Language: English
• Published: 11.08.2020
• Subjects: APPARATUS THEREFOR; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

Described herein is a method for substantially nickel-free phosphating of a metallic surface, wherein a metallic surface, optionally after cleaning and/or activation, is first treated with an acidic aqueous phosphating composition that includes zinc ions, manganese ions, and phosphate ions, and is optionally rinsed and/or dried, and is thereafter treated with an aqueous after-rinse composition that includes at least one kind of metal ion selected from the group consisting of the ions of molybdenum, copper, silver, gold, palladium, tin, antimony, titanium, zirconium, and hafnium and/or at least one polymer selected from the group consisting of the polymer classes of the polyamines, polyethyleneamines, polyanilines, polyimines, polyethyleneimines, polythiophenes, and polypryroles and also mixtures and copolymers thereof, with both the phosphating composition and the after-rinse composition being substantially nickel-free.