Hard Coat (Black/Colors)

Similar process to hard coat clear, “hard coat” or hardcoat anodizing, also known as Type III anodizing, is an electrochemical process that creates a dense and robust aluminum oxide layer on the surface of non-ferrous alloys, primarily aluminum-based alloys.

Most common type III finishes are clear and black, but specialty colors may be made available. Here are the key points in choosing a hardcoat finish:

Purpose:

• Surface Performance Enhancement: Hard coat anodizing significantly improves properties such as surface hardness, abrasion resistance, dielectric strength, and corrosion resistance.
• Thicker Layer: Unlike regular anodizing, hard coat anodizing produces a relatively thick oxide layer (typically 2 mils or 51 µm).
• Ideal for Extreme Conditions: It’s especially useful for aluminum parts exposed to harsh operating environments.

Process:

1.  The aluminum part is immersed in an electrolyte solution (usually sulfuric acid).
2. An electric current causes a chemical reaction, forming the protective aluminum oxide layer.
3. Dyes can be added for aesthetics, although other anodizing methods (like Type II sulfuric acid anodizing) offer more color options.

Applications:

Commonly Used: Aerospace, defense, optics, architectural, manufacturing, marine, automotive and medical industries.

Materials: Aluminum, titanium, and magnesium (with aluminum being the most frequent).

Remember, hard coat anodizing provides durability and extreme protection for critical components over the standard aluminum anodizing process due to its thickness and additional durability.