Surface treatment of aluminum material

Abstract

Abstract PURPOSE:To inhibit the separation of brazed Al materials over a long period even in the case where Zn is sacrificially corroded after brazing, by electroplating each Al material in a plating bath contg. Zn, Fe and NaOH to form an Fe-contg. Zn alloy film. CONSTITUTION:The surface of an Al (alloy) material is cleaned by the conventional method and electroplated in a plating bath contg. Zn, Fe, NaOH and a brightener to form a Zn-Fe alloy film. When such Al materials are brazed, Zn diffusion layers are formed in the surfaces of the Al materials and a Zn-Fe alloy layer is present between the Al materials. Zn in the Zn diffusion layers and the Zn-Fe alloy layer is sacrificially corroded to prevent the pitting corrosion of the Al materials. Even in the case where Zn in the Zn-Fe alloy layer is sacrificially corroded, the separation of the Al materials is inhibited over a long period.

Inventors

• 👤 Yoshifumi Shimajiri
• 👤 島尻　芳文
• 👤 Shoichi Furuta
• 👤 古田　正一
• 👤 Kanji Takasaki
• 👤 高崎　完二
• 👤 Akio Tani
• 👤 谷　昭緒

Bibliographic Details