What are the factors that affect the plating process?
Many metal shells and components on the market are electroplated in order to better use and prolong its service life. Electroplating can be electroplated with different metals, such as zinc plating, nickel plating, chrome plating, etc. There are many elements that affect the quality of the coating, so the factors that specifically affect the quality of the plating mainly include the main salt system, PH value, additives, current density, current waveform, temperature, stirring speed, plating equipment and so on. Some of these factors are discussed below.
1. Main salt system
Each plating type will develop a variety of main salt systems and matching additive systems. For example, galvanization includes cyanide zinc plating, zincate zinc plating, chloride zinc plating (also known as potassium salt zinc plating), Ammonia zinc plating, sulfate zinc plating and other systems.
Each system has its own advantages and disadvantages, such as good dispersibility and depth of cyanide galvanizing solution, fine coating crystals, good bonding with the substrate, good corrosion resistance, wide process range, stable and easy operation of the plating solution. Too sensitive and other advantages. But highly toxic and seriously pollutes the environment. Chloride zinc plating solution is a single salt plating solution without complexing agent, and the wastewater is easy to handle; the brightness and leveling of the coating are better than other systems; the current efficiency High, fast deposition speed; steels with low hydrogen overpotential such as high carbon steel, castings, forgings, etc. are easy to plate. However, due to the weak acidity of chloride ions, it has certain corrosiveness to the equipment, on the one hand, it will cause certain corrosion to the equipment On the other hand, such plating solutions are not suitable for deep holes or tubular parts that need auxiliary anodes.
Additives include gloss agents, stabilizers, softeners, wetting agents, low-zone dislocation agents, etc. The gloss agents are divided into main gloss agents, carrier brighteners and auxiliary gloss agents. For the same main salt system, use different manufacturers The quality of the resulting coatings is very different. Generally speaking, the additives in developed countries such as Europe, America, and Japan are the best, followed by Taiwan, and the mainland production is relatively inferior to the first two.
The combination of the main salt and the additives of a specific manufacturer determines the overall performance of the plating solution used. Excellent additives can make up for the lack of some properties of the main salt. For example, the excellent chloride zinc plating additive and the main chloride salt are combined The deep plating ability of the bath is better than that of many cyanide zinc baths.
3. Electroplating equipment
Hanger: Use the square hanger with the square plating tank, the round hanger with the circular plating tank. The round plating tank and hanger are more conducive to ensuring the uniform current distribution, and the square hanger needs to be added around the hanger. Provide a current-distribution device such as a barbed wire or shorten the length of the anode plates on both sides, and use an oval anode arrangement as shown in the figure.
Stirring device: Promote the flow of the solution, make the solution state evenly distributed, and eliminate the stay of air bubbles on the surface of the workpiece.
Power supply: DC, good stability, small ripple coefficient.
The above is the relevant content about "What are the influencing factors of the electroplating process?" The information is provided by Attractivechina, a 25-year-old spraying production line manufacturer. For more information about the spraying production line, please follow us for updates!