Preparation Of The Additives Of The Satin Nickel Electro-deposition And Study On The Mechanism Of The Formation Of The Satin Nickel Electro-deposition

The ingredients of additives of the decorative satin nickel electro-deposition and the suitable conditions for satin nickel electro-deposition have been ascertained through a large quantity of experiments. The properties and characteristics of the electroplating bath and the coating obtained were investigated. The experimental results show that the additives contain 3 kinds of ingredients, and every kind of ingredient performs different function in the process of the electroplating. The first kind additive is basic brighter of nickel electroplating, the main function of which is to reduce the crystalloid size of nickel coating, to make the nickel coating appear certain brightness, to reduce the stress and to improve the tractility of nickel coating as well. The second kind additive is quaternary ammonium compounds, the main function of which is to maintain the stability of the electroplating bath and prolong the using life of the electroplating bath, different pearl-like effect of satin nickel coating can be obtained with different kind of quaternary ammonium compounds. The third is non-ion surfactant, the main function of which is to make the coating appear satin effect. Different bright effect of satin nickel coating can be obtained with suitable nickel electroplating brighter.Good effect pearl-like satin nickel coating could be obtained in 9~10 hours with the watts nickel electroplating bath, and the additives described in the thesis is in the electroplating bath; without active carbon treating after using, the electroplating bath could be used again with adding suitable quantity of additives after the normal filtrating. The corrosion resistance, wear resistance and hardness of satin nickel coating made with the way in the thesis are favorable, and the coating combined well with the basal object.In the thesis, cathodic process of the satin nickel electroplating with the additives self-made was studied with various electrochemical techniques, the functions of different ingredient of the additives in the process of the satin nickel electroplating and the mechanism of the satin nickel electroplating have also been studied with the methods of scanning electron microscopy, X-ray diffraction, and so on. In the course of electroplating, quaternary ammonium compounds is absorbed on the surface of the cathode, the hydrophobic part of the quaternary ammonium compounds and the small emulsified drops of the non-ion surfactant attract with each other, and the small emulsified drops are absorbed on the surface of the cathode, small pits are formed on...