Chicago Plating, Inc.
(630)718-1600 Fax: (630)718-1690
P.O. Box 164 Naperville IL. 60566
Bill Crawford, President




Anodizing is an electrically applied oxide layer on the surface of an aluminum part. The most common specification is MIL-A-8625, which has three types. Type I Chromic Acid is the oldest type of anodizing and is rarely used. There are some aerospace applications for use as a paint base. Type II Sulfuric Acid is clear when applied but the porous surface can be dyed many colors. Type III Sulfuric Acid Hard Coat has a different grain structure than Type II. Thicknesses of .001 to .0025 are common. It is a dark green as produced, but can be dyed black.