Corrosion Resistance: The aluminum oxide film is resistant to atmospheric and saltwater environments.
Electrical Insulation: Aluminum oxide film is dielectric.
Paint Adhesion: Aluminum oxide film is a chemically active surface for painting.
Adhesive Bonding: Aluminum oxide film improves adhesion and bond strength.
Cleanability: Anodized coatings do withstand hydrogen peroxide commonly used in medical sterilization.
The most common specification governing aluminum anodizing is Mil-A-8625, which denotes three different finishes: Type I, a thin film generated in chromic acid anodizing and used mostly by the aerospace industry for corrosion protection, Type II, the most common form of anodizing produced in sulfuric acid and often dyed different colors, and Type III, or Hard Anodize, which is a thick film that is highly abrasion-resistant due to its surface hardness. CRC offers Chromic (Type I), Sulfuric (Type II), and Hard (Type III) services.