ALUMINUM ALLOY MATERIAL FOR PHOSPHATING AND METHOD FOR PHOSPHATING ALUMINUM ALLOY MATERIAL

摘要

PROBLEM TO BE SOLVED: To suppress the elution of Al ions from the surface of an Al alloy material even if the Al alloy material is treated together with steel products in the same line by providing the surface of the aluminum alloy material with a precoat with is nonreactive with a phosphating bath. ;SOLUTION: The surface of the aluminum alloy material is provided with the precoat film which is nonreactive with the phosphating bath. The nonreactive precoat film refers to the film having the good adhesion property to a resin coating film in a coating stage following the phosphating in addition to the nonreactiveness to the phosphating bath as an essential requirement. The film preferably has weldability and does not hinder the corrosion resistance after coating. The precoat film having such characteristics may be exemplified by a hydrated oxide film of aluminum, chromate film, resin film, films of a lithium salt, magnesium salt, cerium salt, calcium salt, or the like, potassium permanganate film, oxide film of Al by tight adhesion, or the like.;COPYRIGHT: (C)2000,JPO