Meaning of anodized coating in word sense is oxidation of aluminum by using and electrolytic method. This process is also called as Anodic Oxidation or Anodization as well. Purpose of this coating is to increase corrosion resistance of aluminum and adding an aesthetic look. Appropriate type of coating must be selected according to scope of the application. Paint adhesion and light fastness in anodized coatings are done according to customer needs.
Chromic Acid Anodizing
In spite of its thin surface coating it has high corrosion resistance and shows surface defects, it also has high performance in paint adhesion. It is mainly preferred in aerospace industry due to these benefits. Coating thickness is between 0,5-17 µm values.
Performance Tests
Coating performance is calculated by Coating Weight and Corrosion Resistance tests.
Related Standards
MIL-A-8625F Type I: Class 1 and Class 2 (These are the main international standards, it can also be customer standards as well.)
Sulphuric Acid Anodizing
Mainly used in areas where high corrosion resistance and decorative features are needed. Coating thickness is between 1,7-25 µm values.
Performance Tests
Coating performance is calculated by Coating Thickness, Coating Weight and Corrosion Resistance tests.
Related Standards
MIL-A-8625F Type II: Class 1 and Class 2, DIN 17611 (These are the main international standards, it can also be customer standards as well.)
Hard Anodizing
It is used where the high friction and wear resistance, corrosion resistance and high coating thickness are needed. Coating thickness is between 12.5-110 µm values.
Performance Tests
Coating performance is calculated by Coating Thickness, Coating Weight, Corrosion Resistance and Abrasion Resistance Tests.
Related Standards
MIL-A-8625F Type III: Class 1 and Class 2 (These are the main international standards, it can also be customer standards as well.)
Not every aluminum alloy is suitable for anodizing. Appropriate series varies according to industry and type of anodizing. Anodizing is a process which totally shows the metallic structure of an aluminum alloy therefore it is also possible to change the shape of the surface lines and can be made matte by mechanical or chemical etching. These are mostly for decorative purposes.