Anodize (Chromic & Sulfuric)
Anodize (Chromic & Sulfuric)
Conventional Types I, IB and II anodic coatings are intended to improve surface corrosion protection under sever service conditions, or as a base for paint systems. Coatings can be colored with a large variety of dyes and pigments. Type I and IB coatings should be used on fatigue critical components due to thinness of coating.
Type IC and IIB coatings provide non-chromate alternatives to Type I and IB where corrosion resistance, paint adhesion and fatigue resistance is required.
Type I, unless otherwise specified, shall not be applied to aluminum alloys with over 5.0% copper, 7.0% silicon or total alloying constituents over 7.5%
Coatings shall meet weight requirements in table l of MIL-A-8625 prior to dying or sealing. Class of anodic coating and any special sealing requirements shall be specified prior to processing parts.
MIL-A-8625
Type I
Chromic acid conventional anodizing. Nominal thickness ranges from 0.0002" to 0.0007".
Type IB
Chromic acid low voltage process anodizing (22v 2v). Nominal thickness ranges between 0.00002" to 0.0007".
Type IC
Mineral or mixed mineral/organic acid anodizes. Provides a non-chromated alternative for Type I and IB coatings.
Class 1
Non-dyed
Class 2
Dyed. Specify color on contract.
Type IIB
Thin sulfuric acid anodize for use as a non-chromated alternative for Type I and IB. Nominal thickness ranges between 0.00002" to 0.0007"