Study On Environment-friendly Protective Agents Of The Coating

The plating of copper, nickel and tin are widely used for their excellent performances. However, because the coating is mixed up with so many kinds of impurity that it is easy to be discoloration and corrosion, then it will affect the performance of the coating. Therefore, the protective agents of the coating are applied. At the present time, the protective agents couldn't give consideration to solubility, corrosion resistance, appearance, conductivity and environment protection. To overcome the shortcomings, quantum chemical simulation could be applied in the study of the theory on protecting according to the mechanism of corrosion. On the basis of the preservation of performance on the coating, the protective agents which were with good resistance to corrosion, water-soluble and environmental would be studied. The main contents and conclusions in the thesis are listed as follow:1.S and N have been as the adsorption group to establish adsorption model. Quantum chemical simulation has studied the adsorption on the copper and nickel, adsorption model could be build by configuration of the adsorption.2.The corrosion test of 3% sodium chloride and high temperature test on 200℃were used to filter the agents on the copper selected from literatures, then agents was further filtered by the orthogonal test, finally the agents was acted in concert with others to obtain BCu-10. The coating appearance, porosity, hydrogen sulfide accelerate corrosion and contact resistance of the coating protected by BCu-10 met the requirements. Electrochemical testing displayed that it could form a chemical adsorption film on the copper. The X-ray photoelectron spectroscopy provided that the elements of protective film on the coating were Cu, O, N, C and S. It was not poisonous and harmful and it's also through environment testing by Societe Generale de Surveillance S.A. (SGA).3.The porosity test was used to filter the agents on the nickel selected from literatures, then agents was further filtered by the appearance and neutral salt spray test, finally BN-96A was chose. The coating appearance, porosity, hydrogen sulfide accelerate corrosion and contact resistance of the coating protected by BN-96A met the requirements. Electrochemical testing showed that it could form a physical adsorption film and chemical adsorption film on the nickel. The X-ray photoelectron spectroscopy provided that the elements of protective film on the coating were Ni, O, N, C and S. It was not poisonous and harmful. It's also through environment testing by SGA.4.The corrosion test of cysteine solution and high temperature test on 260℃were used to inspect the anti-tarnish performance so that the agents on the tin was to be filtered, in the end, D was chose, then the agents was acted in concert with others to obtain BSn-2006A. The coating appearance, porosity, hydrogen sulfide accelerate corrosion and contact resistance of the coating protected by them met the requirements. The result of X-ray photoelectron spectroscopy provided that the elements of protective film protected by BSn-2006A were Sn, O, N, Cand P.It was not poisonous and harmful.