Anodic oxidation coating with significantly higher wear resistance and hardness than original or clear anodized material. The thickness is 15 to 75 μm according to the type of material. It significantly improves the functional properties and prolongs the life of aluminum parts.

Technical details

  Hard anodizing
Layer thickness 20-80 µ
Color According to alloy type - dark gray, bronze, brown, green
Hardness 370 - 600HV
Specification by standards ISO 10074
STN EN 2576
ISO 10074
STN EN 2536
DEF STAN 03-25


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Advantages of hard anodizing:·

  • Excellent wear resistance
  • High hardness
  • Excellent corrosion resistance
  • Suitable as a base layer for sliding varnishes
  • Thermal resistance of the layer up to the melting temperature
  • Electroinsulating properties even at temperatures up to 500 °C
  • Flawless adhesion of the layer to the base material


  • Uncolored – it has a color whose hue is heavily influenced by the type of alloy and layer thickness and ranges from pale gray to olive green to dark brown.
  • Black anodized – anodized coating is additionally dyed by black paint.
  • Sealed - originally porous anodized layer is sealed in order to improve corrosion resistance. However, when sealed in hot water, the hardness of the layer abrasion is reduced. In cold sealing the pores are closed by metal ions and the mechanical properties of the layer do not change.