Hard Coat Anodizing - Type III

Anodize hard

Finish Name

Hard Coat Anodizing - Type III
Hard Anodizing
Aluminum Anodizing, Type III
Aluminum Anodizing, Hard
Anodizing, Hard Coat, Type III
Specialty Hard Coat Anodizing and Teflon Seal
Anodize hard picture 1
Anodize hard picture 2


Type III Hard anodizing is used when an increased wear and abrasion-resistant coating is needed. The aluminum oxide coating is thicker than regular anodizing, which gives the metal surface additional protection.  Parts can be processed at lower temperatures, but increased electrical flow is required.

Suitable for

Specialty Fastners
Functional or Decorative

Industry use

Military and Defense
Flight Critical

Base metal substrate

Aluminum alloys
2024 Aluminum alloy
6062 Aluminum alloy
7075 Aluminum alloy


Color: charcoal gray to slightly green
Optional Finish: Black Dye

Seal Options

Hot Water
Nickel Acetate
Teflon seal


MIL-A-8625 Type III




  • Provides extreme abrasion resistance in coatings having .0005" to .002" thicknesses.
  • Provides lubricity hard anodize aluminum oxide abrasion resistant surface.
  • Provides excellent corrosion resistance.
  • Can be color dyed. Pending the alloy, the natural color is charcoal gray to slightly green hue, with no seal.
  • Can be Teflon impregnated.
  • Hard Anodize aluminum oxide coating functions and has the feature of being an electrical insulator.

What are the attributes / characteristics of Hardcoat Anodize?

  • Increased abrasion resistance (best when unsealed)
  • Increased wear resistance.
  • Increased corrosion resistance (best when sealed)
  • Improved aesthetics (see effect)
  • Dielectric properties (coating is an electrical insulator)

Note: We provide Chromic Anodizing Type I, Sulfuric Anodizing with Color - Type II, Hard Anodizing Type III, and Sulfuric Anodizing - Type II.