COMPOSITE NON-CHROMOUS CONVERSION COAT FOR PARTS MADE FROM ALUMINUM ALLOYS AND METHOD OF FORMING SUCH COATS (VERSIONS) Russian patent published in 2004 - IPC

FIELD: corrosion protection of parts made from aluminum alloys. SUBSTANCE: proposed method includes preparation of first solution containing agents of anode inhibitor type, preparation of second solution containing agents of cathode inhibitor type and immersing the part to be coated into in first and second solutions. Agents of anode inhibitor type include tungstates, permanganates, vanadates, molybdates and their mixtures. Agents of cathode inhibitor type include cobalt, cerium and other lanthanide elements and their mixtures. According to one of versions, conversion coat is formed with use of solution containing cerium and solution containing tungstate. EFFECT: 10-fold increase of corrosion resistance. 17 cl, 1 tbl, 1 ex