abstract |
A method for surface treatment of aluminum alloy to form a uniform and dense zinc phosphate coating, which has excellent corrosion resistance properties on the surface of the aluminum alloy. The method includes steps of surface adjusting the surface of the aluminum alloy by a surface adjustor containing a predetermined volume of zinc phosphate particles, copolymer containing carboxylic acid group, and natural hectorite and/or synthetic hectorite respectively, and chemical conversion treating the surface of the resultant aluminum alloy by a zinc phosphate treating agent containing a predetermined volume of chelating agent that can chelate bond with iron ion. |