Study of Zincating and Electroless Nickel Plating on 2A11 Aviation Aluminum Alloy

• 1、College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410012

Abstract：Aluminum alloy has broad commercial application prospects in aviation, automobile, electronics and other fields because of its many excellent properties. Nowadays, application in harsh aviation environments puts forward higher performance requirements for aluminum alloy. However, due to the active chemical nature of aluminum, direct application without treatment will limit the advantages of aluminum alloy. In order to overcome the shortcomings of aluminum alloy surface performance, surface treatment technology appears to solve or improve various problems in aluminum alloy applications.Study on the Process of Zinc Dipping and Electroless Nickel Plating for 2A11 Aviation Aluminum Alloy very important. In this paper, electroless nickel plating was used to treat the surface of 2A11 aluminum alloy to prepare a low-phosphorus-medium-phosphorus-high-phosphorus gradient composite coating. In the pre-treatment, the zinc immersion process is mainly studied, and the morphology, bonding force and corrosion resistance of the coating layer are tested under different zinc immersion conditions. The properties of low-phosphorus, medium-phosphorus and high-phosphorus coatings prepared under different process conditions are analyzed. The optimal zinc dipping process conditions and the optimal combined electroless nickel plating process conditions were obtained through experiments. The optimal zinc dipping process conditions are the dipping temperature of 20-25℃, the first dipping time of 60s, the dezincification of 10s, and the second dipping time of 30s. The optimal combined electroless nickel plating process conditions are low-phosphorus plating at 40℃, 10min; medium-phosphorus plating at 90℃, 1h; high-phosphorus plating at 90℃, 2h.

Keywords： Physical chemistry Aluminum alloy Pretreatment Zinc dipping Electroless nickel plating