Preparation And Properties Study Of Electroless Ni-Cu-P Deposition On Aluminum Alloy

In this paper, the electroless plating technology of the Ni-Cu-P alloy coatings on the aluminum alloy substrate were studied. By means of XRD,SEM,EDS etc. the content, morphology, and structure of the Ni-Cu-P alloy coating were analyzed. The main content of the experiments and the results included:1. The optimized plating bath formula and plating parameters of the electroless Ni-Cu-P alloy deposits was discussed. The effect of the thickness, corrosion resistance and porosity on the plating parameters, such as temperature, pH value, the concentration of NaH2PO2, CuSO4 and C6H5O3Na3 was investigated.2. The adhesion of the the Ni-Cu-P and Ni-p alloy coatings was studied by nicking test. Result shows that the adhesion of the two coatings are nearly the same.3. The resistance of the the Ni-Cu-P and Ni-P alloy coatings was tested with the method of four probe. The result showed that the resistance of Ni-Cu-P coating was lower than the Ni-P coatings, and the possible reason was studied.4. With the method of alternating current resistance and polarization curve, the corrosion resistance of the two coatings was studied, the results indicated that the corrosion resistance of the Ni-Cu-P coating is better than the Ni-P coating, and the anti-corrosion mechanism was discussed.