2019/Oct/15
Daily Message :
Be faithful to that which exists within yourself.

Green - Chromate Coating of Aluminium

Green chromate coating is a type of trivalent coating that provides a good paint adherance and corrosion protection on aluminium surfaces. The surface to be coated has to be free from grease or oxidation layers for a proper coating. Green chromate coating is made in acidic solution therefore treatment bath must be made of stainless steel or PP. Green chromate coated aluminium surface can range in color from mate to iridescent green. Despite depositing trivalent chromium on the surface, coating solution consists of hexavalent chromium ions, hence purification has to be done while discharging of coating baths.

REMOLINE G 11/12 - Green Aluminium Chromate Coating
REMOLINE G 11/12 is a two component green chromating process for the coating of aluminium and its alloys by immersion application. Color of the coating is light green to iridescent green. Coated surface has excellent corrosion resistance and bonding ability of subsequent paintings. Coating solution includes hexavalent chromium (Cr+6) but coating itself consists of mostly trivalent chromium (Cr+3) which is highly preferable than hexavalent coating because of human health and environmental and concerns. Metal surface has to be degreased and etched before going in chromating. 40 - 55 °C degree of temperature is enough to obtain proper coating of green chromate. Treating time in coating soultion can vary in the range of 3 - 10 minutes according to chromium concentration and treating temperature. Green chromate coated parts are rinsed with deionized water and then they are dried at temperatures not above than 70 °C.