Anodizing is an electrochemical process used to coat aluminum in an oxide layer and give it color. It creates a protective layer known as an anodic oxide finish. This layer improves the appearance and durability.
The anodizing procedure involves submerging the aluminum piece into an acid solution, usually sulfuric or oxalic acid. This is called an anodizing bath. The metal then acts as an anode while the electrons flow out of it. As the electrons move, they create an oxide layer on the surface of the aluminum. This oxide layer protects the aluminum from wear and tear. This new aluminum oxide layer is fully integrated into the underlying substrate of the material. As a result, it is resistant to chipping or flaking off unlike a painted surface. The oxide layer has a very porous structure allowing it to take color and sealant well. You can achieve some very vivid colors.
By controlling the process and adding anodizing dyes to the bath, you can achieve a variety of colors. Aside from aesthetics, anodizing increases the resistance to corrosion. This makes anodized aluminum pieces much more durable than uncoated components. If done correctly, anodizing is a fairly easy and cost-effective way to protect aluminum parts.
Aluminum is the most common metal to anodize. There are other nonferrous metals that can also be anodized such as magnesium and titanium.
Anodized aluminum parts can be used in many industries from manufacturing and automotive to marine and aerospace applications. Anodizing aluminum is a crucial process for maintaining and ensuring the integrity of parts exposed to the elements or wear and tear. With proper maintenance, anodized aluminum parts will last for many years.