What should be noticed in the surface treatment of sheet metal parts during the processing? After all, the appearance of beauty can cause customers to purchase the desire, so, surface treatment is very important.
1. Note that the status of the workpiece, all the electrochemical processing must be in the workpiece in the part of the body, the combination of the components feel that can not be electrochemical treatment. Because in the process of processing, the solution will be trapped in the gap of the Assembly and the workpiece corrosion.
2. Attention should be paid to the processing sequence problems, such as the parts of the spot welding can be chemically treated, but must not be electrochemical treatment, including electroplating, anodic oxidation of electrochemical treatment will affect the quality of spot welding. For some electroplating or oxidizing parts with riveting requirements, the machining process must be followed by electroplating or oxidation before riveting.
3. Attention should be paid to pretreatment before surface treatment, such as steel parts before spraying, it is necessary to undergo phosphating treatment, so as to increase the adhesion of the coating. Nickel-plated steel pieces, in order to improve its corrosion resistance, you can first plating a layer of copper or dark nickel bottom. Zinc base alloy also exists this problem, before electroplating also need to be plated with a layer of copper or dark nickel bottom, this can improve the adhesion of the plating layer.
4. To pay attention to the workpiece material and treatment methods can not conflict, aluminum alloy castings will not allow the oxidation of sulfuric acid anodizing treatment.
5. According to the shape of the parts to determine whether it is suitable for electrochemical processing, for example, the length of a slender tube with a diameter greater than twice times is not suitable for electrochemical treatment, because the inner surface of the film can not form a high quality, but with a deep groove or a depth greater than twice times the diameter of the fine hole of the parts, after electroplating, the inner surface can not be completely covered
6. Also pay attention to whether the matrix material and the coating material conflict, because most organic gases have corrosive effect on zinc, so in the design of sheet metal processing should be carefully selected galvanized layer and organic material contact or assembly in the same airtight body.