Ecreative logo

Anodic Coatings

Time to Read: 1m 8s

Anodic Coatings, also known as anodized coatings, can be added to metal materials to increase the metal’s corrosion resistance and wear resistance, improve its adhesion to primers, glue, and paints, reduce galling in threaded components, and increase the hardness of the metal’s surface. Anodic coatings can also be added for aesthetic purposes, including dying and coloring of the material. Aluminum is the most commonly coated metal, though processes for anodizing titanium, zinc, magnesium, niobium, zirconium, hafnium, tantalum, and other metals also exist. Anodic coatings are created through an electrolytic passivation process. A variety of different processes can be used to deliver different results, but all anodizing processes are essentially the same. The metal item to be coated is soaked in a specially formulated acidic solvent bath, to which direct current electricity is applied. The part being treated forms the anode electrode of the resulting electrical circuit, hence the term “anodizing.” Type I anodic coatings utilize a chromic acid mixture. Type II and Type III (also known as hardcoat anodizing or