Electro-galvanizing, also known as cold-galvanizing in the industry, is the process of forming a uniform, dense, well-bonded metal or alloy deposit on the surface of the part by electrolysis.
Compared with other metals, zinc is a relatively inexpensive and easily plateable metal. It is a low-value anti-corrosion coating that is widely used to protect steel parts, especially to prevent atmospheric corrosion, and is used for decoration. Plating techniques include slot plating (or rack plating), barrel plating (for small parts), blue plating, auto plating and continuous plating (for wire and strip).
Influencing factor：
(1) Effect of zinc content
The zinc content is too high, the brightness range is narrow, and it is easy to obtain a thick plating layer, and the iron content in the plating layer is lowered; the zinc content is too low, the brightness range is wide, and it takes a long time to reach the required thickness, and the iron content in the plating layer is high.
(2) The effect of sodium hydroxide
When the sodium hydroxide content is too high, the high temperature operation is easy to burn; when the sodium hydroxide content is too low, the dispersing ability is poor.
(3) The effect of iron content
The iron content is too high, the iron content in the coating is high, the passivation film is not bright; the iron content is too low, the iron content in the coating is low, the corrosion resistance is lowered, and the color is olive-colored.
(4) The effect of brightener
ZF-IOOA is too high, the coating is brittle; too low, no plating in the low current area, uneven passivation color; ZF-100B is too high, the coating is brittle; too low, the entire coating is not bright.
(5) The effect of temperature
The temperature is too high, the dispersing ability is lowered, the iron content in the plating layer is high, the corrosion resistance is lowered, the color of the passivation film is uneven, and the flower is formed; the temperature is too low, the high current density region is burnt, the plating layer is brittle, and the deposition speed is slow.
(6) Influence of cathode movement
Cathode movement must be used. Moving too fast, the coating in the high current density region is rough; too slow, it may generate airflow, and there is no plating at all.