Hard anodizing is a thick-film anodizing method, and the process is roughly the same as ordinary anodizing. It has high wear resistance, heat resistance, and insulation. The breakdown voltage reaches 2000 volts. It is widely used in the defense industry and other mechanical parts.
Difference between hard anodizing and ordinary anodizing
1. Film thickness. Ordinary oxide layers are relatively thin. The thickness of the hard anodized film is greater than 15 microns, and the theoretical maximum thickness can reach 250 microns.
2. Surface condition. The ordinary anodized surface is relatively smooth, while the hard anodized surface is relatively rough (microscopic, related to the surface roughness of the substrate)
3. Porosity. The porosity of ordinary oxidation is higher than that of hard oxidation.
4. Ordinary oxidation is a transparent film. Because the hard anodized film is relatively thick, it is an opaque film.
5. Using environment. Ordinary oxidation is tried for decoration. Hard anodizing is function-oriented. Generally used in wear-resistant and electric-resistant environments.
At present, most manufacturers use hard anodizing to replace the traditional hard chrome plating. Compared with hard chrome, it has the advantages of low cost, firm film bonding, and convenient treatment of plating solution waste.
The disadvantage is that when the film thickness is large, it will affect the mechanical fatigue strength index of aluminum and aluminum alloys.
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Post time: Jun-13-2022