For environmentally friendly metal coating, I believe we are not yet particularly aware of the common problems of environmental protection metal coating in the process you know how much? What are the characteristics of coating?
Environmentally friendly metal coating process is to make the raw materials into water-soluble coating solution, and then directly coated on the activated surface of the workpiece, after drying, sintering to form a layer of inorganic film. Green metal coating process of the common problems do you know?
1, the instability of coating solution: As zinc powder density is relatively large, easy to settle when the configuration of the coating, the coating solution stratification, for which must choose efficient thickener. The use of sodium polyacrylate coating thickening, when added in excess, the coating is very easy to gel, thereby shortening the service life. From the coating liquid life and productivity are not suitable;
2, coating the surface color: coated with advanced materials after the workpiece, the treated surface color is silver white. Found in the production process, the ratio of zinc powder and aluminum have a greater impact on the color, increase the amount of aluminum powder can increase the silver-white parts. After the amount of aluminum powder increases, the corrosion resistance of the workpiece has a certain impact;
3, chromic acid pH effect: Dacromet coating solution, there is a component that must be considered, namely chromic acid solution. In the actual preparation process, if the chromic acid pH value is high, the chromic acid and the slurry reaction is very intense, release a lot of heat, and finally make the entire solution system caking, failure. If diluted with water after coating, the workpiece surface adhesion decreased, easy peeling;
4, stirring time on the quality of zinc-chromium coating: dacromet coating liquid ingredients must be stirred to make the slurry mixed with chromic acid and other components and the reaction curing. With a good coating fluid has a useful life, stored in a closed container, and kept stirring, can be used for 3 days;
5, the impact of wetting agent: Dacromet coated parts are steel parts, wetting the coating surface in the workpiece, spreading good or bad, directly affect the quality of the layer. If wetting, spreading is not good, will make the workpiece surface slippery, multiple coating to cover the workpiece surface, resulting in uneven coating dacromet coating, dacromet coating process common problems do you know? Corrosion resistance is reduced.
The above is the entire content of environmentally friendly metal coating, and want to know more information, please call detailed inquiry.
