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Sulfuric Vs. Hardcoat Anodizing

Anodizing is the process of finishing aluminum to provide a resistant coat on the metal. There are a number of ways for anodizing to occur, but they do share some common qualities. Anodizing is durable, prevents metal from corrosion, and is an environmentally-friendly option for finishing metal. Anodizing is also a cost-effective method of finishing metal. Take a look at the differences between two of the most popular varieties of anodizing we can do, and understand when anodizing is perfect for you.

Sulfuric Anodizing

Sulfuric acid is used in this process to create an anodized coating for the metal. The coating is extremely thin, usually ranging from 0.001-0.0001 inches thick. The result of this coat is a porous surface, so the metal can absorb colored paints and dyes with ease. This is a preferred method of coloring metal so the color lasts for years. Sulfuric anodizing is also a relatively cheap method of anodizing and creates less waste. This means it’s a favorable choice for many people.

Hardcoat Anodizing

This coating also uses sulfuric acid but creates a much thicker coating for the metal. The surface is hard and durable, meaning it’s perfect for heavy use. Hardcoats are also non-conductive, meaning that it’s excellent for electrical insulation. The thickness of the coating means it can also be used to fix worn aluminum components.

A common misconception is that hardcoat anodizing is a variety of sulfuric anodizing. Although they both use sulfuric acid as a method of creating the anodized coating, the thickness of each coating and the durability differentiates them. When you need anodizing for your aluminum, then you should be sure which option is perfect for you. If you’re still not sure, contact AOTCO for support in figuring out what you need. We’re here to make sure your metal finishing process is simple and easy for you.