China's zinc plating (also called galvanizing) technology has been very mature in the development of many years, the current zinc plating technology is mainly divided into acid zinc plating and alkaline zinc plating. Potassium chloride galvanizing is acid zinc plating, alkaline zinc galvanizing is alkaline zinc plating, then which one should we use in the galvanizing process? Many friends will ask such question. Let's explain the difference, advantages and disadvantages of the two as following.
Prior to acid zinc electroplating, the plated parts are first subjected to pickling, water washing, etc., and then placed in a galvanizing bath for electroplating.
Advantages of acid galvanizing
1. Bright color and metallic texture
2. Fast plating speed, low cost and high daily output
Disadvantages of acid galvanizing
1. Poor adhesion of galvanized layer and it is easy to peel off (shedding)
2. Poor anti-corrosion effect, easy to rust in multiple test tests.
3. It is easy to passivate, and as time goes on, the bright color will easily fade.
4. The galvanized wastewater and heavy metal ions are seriously polluted.
Alkaline zinc plating or galvanizing, also known as cyanide-free galvanizing, does not contain highly toxic substances and does not corrode galvanizing equipment or barrel plating equipment. The national environmental protection department is constantly increasing its environmental protection, and cyanide-free galvanizing will gradually replace cyanide galvanizing.
Advantages of alkaline galvanizing
The combination of galvanized layer and plated parts is good, and it is not easy to fall off.
It seems to be good, and it can reach 84 hours in strong acid test.
The passivation film has good adhesion effect and is not easy to change color.
Disadvantages of alkaline galvanizing
1. The pretreatment process in the early stage of galvanizing is complicated, and the quality of pretreatment is high.
2. Low production efficiency and low daily output
3. A pungent gas is emitted during the galvanizing process.
4. The bright brightness after galvanizing is slightly worse.
Through the above introduction, we believe that everyone has a certain understanding of acid galvanizing and alkaline galvanizing. Products after acid galvanizing are generally unable to meet RoHS, which is marked by the “Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment”, so alkali zinc plating will be the first choice if the products need to meet RoHS.
Highnic Group's subsidiary I.M.T. provides non-cyanide alkaline zinc plating process completely free of cyanide,safe and environmental-friendly with excellent dispersive ability leaving an even thickness of deposit on the workpiece. The deposit is ductile and easy to have chrome passivation and further processing. The process is stable and of high tolerance against temperature and impurities. The plating bath is simple, stable and easy to maintain, suitable for both rack and barrel plating.
Previous: How To Do Metal Plating On NdFeB Magnet?