Hardcoat Anodizing / Hard Coating: Things to Consider

Hardcoat Anodizing / Hard Coating: Things to Consider Hardcoat Anodizing, Anodic Oxide Coating, Corrosion / Electrical / Temperature Resistance, Low Coefficient of Friction

Hard coatings (Architectural Type III) offer unique benefits, but have a few attributes that limit their uses. Hard coatings are used when strength and hardness are more important qualities than aesthetics. But there are other considerations to take into account.

For one thing, available hard coat colors are more limited than with Type I or Type II coatings. Hardcoat anodizing is also a more expensive process than Chromic or Sulfuric anodizing. You need to balance the benefits with the additional expense to decide if it's the right choice.

Hard Coating Aluminum: Things to Consider

These are a few things to consider when planning to use  hard anodize (anodic) coatings:

• The application, or end-use, of the component - does it warrant the expense of hardcoating?
• Environment of use:
  • Indoors or outdoors
  • Extreme heat or cold
  • Exposure to direct sunlight
  • High moisture / humidity
  • Corrosive (salt) atmosphere
• The aluminum alloy and temper to be used – only certain alloys can be hard-coated
• Corrosion resistance and hardness specifications
• Desired finish color - fewer choices than
  with other anodizing options
• Thickness range of the film
• Final dimensional tolerances
• Optimum location for contact points (i.e., racking)
• Approval requirements and/or other standards