Zincate zinc plating is a fast developing zinc plating process in the past 30 years. Its main components are main salt zinc oxide, complexing agent and conducting salt sodium hydroxide (commonly known as sodium hydroxide). In order to obtain a fine bright coating with good dispersing ability, a brightener should be added. The main development period of zincate zinc plating in China is in the 1970s when cyanide free zinc plating was carried out. The famous DPE zinc plating process and de zinc plating process have been used up to now. Although this process is not as stable and meticulous as the cyaniding galvanizing process. But its biggest advantage is no cyanide. The harm to the environment is much smaller. Now zincate zinc plating has a new development, blistering and brittleness and other defects have been overcome, the dispersion ability has been greatly improved, and can be compared with cyaniding zinc plating.
Potassium chloride (or sodium chloride) zinc plating process is a new cyanide free zinc plating process developed in 1980s. Its main components are: zinc chloride as the main salt, the general use content is 70-909 / L. Potassium chloride is used as a conductive salt, and its content varies from 140-2809 / L. it can be adjusted according to different needs. Boric acid is used as pH buffer to stabilize pH value between 4.6 and 5.4. Because the bath works at room temperature, the solubility of boric acid is not high, and the content of boric acid is generally controlled at 25. 309 / L.
These three components alone can not produce qualified zinc coating. Some additives should be added to obtain a bright and delicate zinc coating.
The advantages of KCl zinc plating are stable solution, bright and meticulous coating, low cost, high current efficiency and non-toxic. The disadvantage is that the dispersion ability of the plating solution is slightly worse than that of alkaline zinc plating, and the brittleness of the coating is also greater. However, the appearance of KCl zinc plating immediately became popular. The development is very rapid.