Powder coatings perform comparably to liquid coatings of the same resin chemistry and are available in an increasingly wide range of colors. Powder coating serves a growing market and is expected to play a significant part in the finishing of aluminum profiles in the years to come. The resultant finish shows off the natural luster of the aluminum substrate. The anodic finish greatly increases the resistance to corrosion and abrasion over a mill-finished product, without altering the texture of the metal's surface. Etching takes place in a hot caustic solution and yields a matte or satin finish that can diminish the effect of die lines.
Electrical current is passed through the solution while the temperature is carefully controlled.
The electrically-conductive aluminum profile serves as an anode, the result of which is that oxygen ions are released from the electrolyte and drawn to the surface of the aluminum. The oxygen immediately combines with the surface aluminum to form a hard aluminum oxide film. Unlike other finishes, in which a separate coating is applied, the anodic coating is an integral part of the aluminum surface, since it is formed by oxidation of the surface atoms themselves. There are Several Types of Anodizing Anodizing processes differ by type of electrolyte solution used, voltage and current density applied, and bath temperature. The Sealing Step Sealing the anodic pore enhances the beauty and durability of the anodic coating.