SURFACE TREATMENT
Galvanization
Galvanization
What is galvanization？
It is utilized in a wide range of fields as a typical rust prevention treatment. In addition to being especially effective in rust prevention on iron, advances in plating bath and chromate treatment resulted in improved performance on appearance.
Plating bath
We adopt zincate bath. In general, the types of bath shown in the table below have been put into practical application, and the optimal bath is selected for the material, shape, finish appearance and so forth. However, it is important to instruct the proper plating specifications that suit the purpose of use and the environment, as the corrosion resistance varies dramatically due to the plating film thickness and the method of postprocessing.
Types of plating bath and characteristics
| Type | Characteristics |
|---|---|
| Cyanide bath | The most general bath which has been popular since the early times. It addresses good secondary workability and excels in film uniformity and thus is appropriate for small pressed items and objects with complex shapes. |
| Zincate bath | An alkali bath which is the cyanide bath from which cyanide has been removed, and it has gained popularity rapidly in the recent years. It excels in plating film uniformity and thus is applied to pressed items, bolts, nuts and so forth. |
| Acidic bath | It has a better current efficiency than the above two types and generates little hydrogen brittleness in plating. Especially suited to plating on iron alloys and iron castings. |
Chromate treatment
Since galvanized surface is relatively more susceptible to discoloration and corrosion than other plating types without any additional processes, chromate treatment is executed as postprocessing. An outline on the chromate treatment of our company is provided below.
| Type of chromate (galvanization thickness approx.. 8 to 15μm) | ||||
|---|---|---|---|---|
| Type | Color tone in appearance | Characteristics | Corrosion resistance (salt spray) |
|
| Bright chromate (glossy chromate)  |
Trivalent chromate (chromate containing trivalent chromium as an alternative to hexavalent chromium chromate) |
Bluish silver-white | Used for parts for which corrosion resistance is not considered important, as it gives beautiful appearance. | 24h or longer until white rust generation |
| Chromate (colored chromate)  |
Trivalent chromate | Pale yellow | Most popularly used, and has good corrosion resistance. | 72h or longer until white rust generation |
Black chromate |
Corrosion-resistant trivalent chromate | Black | Delivers good corrosion resistance and also used for decorative parts. | |
CONTACT
Expert on plating and surface treatment.
We also handle large products in our electrolytic polishing plant, which is one of the largest in the country.
AKITA KAGAKU Co., Ltd.
81 Idojiri, Hirasawa, Nikaho City, Akita 018-0402
(C) AKITA KAGAKU KOGYO Co.,Ltd.