Galvanizing, also known as cold galvanizing in industry, is a process that uses electrolysis to form a uniform, dense, and well bonded metal or alloy deposition layer on the surface of parts.

Compared to other metals, zinc is a relatively inexpensive and easy to electroplate metal. It is a low value anti-corrosion coating widely used to protect steel parts, especially to prevent atmospheric corrosion. It is also widely used for decoration.

1、 Principle

Because zinc is not easily changed in dry air, while in humid air, the surface zinc forms a very dense layer of zinc carbonate film, which can effectively protect the interior from corrosion. When the coating is damaged for some reason and exposes a moderate amount of substrate, zinc and steel substrates will form microbatteries, and the fastener substrate will become the cathode and be protected.

2. Performance characteristics

Zinc coating has many good characteristics. Thick, fine crystalline, uniform without pores, good corrosion resistance, etc. The zinc layer after galvanizing is relatively pure, and it corrodes slowly in acidic and alkaline mist, which can effectively protect the fastener substrate. After chromic acid passivation, the zinc layer will form various colors, which are both beautiful and decorative. Such as white, colored, military green, etc. Due to its good ductility, the galvanized layer can be cold drawn, rolled, and bent without damaging the coating.

3、 Scope of application

The field of galvanizing is becoming increasingly widespread. The application of fastener products has expanded to fields such as machinery, galvanized chain link fences, electronics, precision instruments, chemical engineering, transportation, aerospace, etc.

Rainbow galvanized

Rainbow galvanizing is a rainbow colored passivation film obtained by treating the galvanized layer once in a chromate solution. The main color is yellow.

Transparent galvanized

Galvanized fasteners

Rainbow galvanized parts

The structure of a typical thin film is a complex mixture composed of basic chromium chromate and basic zinc chromate, chromium chromate, zinc chromate, zinc, and chromium oxides. After passivation treatment, the galvanized layer appears rainbow colored, which can greatly improve its corrosion resistance. Color galvanizing is mainly used for the protection of steel parts.