Though most people don’t know what anodized aluminum is, they see examples of it everywhere around them. It is common in the automotive, aerospace, defense, and electronics industries. You can see it on storefronts, roofs, refrigerators, ranges, televisions, microwaves, and many Apple products.

Choosing the Right Type of Anodizing

(Pixabay / analogicus)

Anodizing is an electrochemical process that turns a metal surface into a more durable, corrosion-resistant, and aesthetically pleasing surface. It is most often applied to aluminum, but it could also be applied to other nonferrous metals (non-iron containing), such as magnesium and titanium.

Anodizing involves a heavy oxidation of water and sulphuric acid that is applied with a negative/positive charge. This is the opposite of other plating processes, such as those performed by gold plating systems, which rely instead on a positive/negative charge.

There are two main anodizing processes, known as hard coat and clear. The one you choose will depend on the intended use of the component to be anodized. Here’s a closer look at the two types of anodizing.

  • Hard coat: This coat is very smooth and hard, and the result is a black-colored coating. It is most often used on machine parts that need to be able to resist friction and abrasion.
  • Clear coat: Clear coating is more popular than hard coating because different colors can be applied to it. It is a heavier type of oxidation and resists corrosion. As such, it is used to coat features or components that need to be shielded from corrosive elements, such as medical instruments that may be exposed to bodily fluids and outdoor architectural elements.

To add durability or style, or both, to aluminum components, anodizing is a great choice. Both types of anodizing offer benefits; which one you choose depends on the nature of your project.