Hard Anodising
What is Hard Anodising?
Hard Anodising (Hardcoat) is an electrochemically produced layer of aluminium oxide on the surface of aluminium. A controlled thickness can be obtained from just a few microns up to 120 microns depending upon the alloy used.
The process is used to produce much thicker, harder and corrosion resistant coatings than the Sulphuric Acid process. The thickness can be very closely controlled, and the cool operating temperature of the process prevents thermal or physical distortion of precision engineered parts or equipment.
Secondary treatments such as impregnation with solid film lubricants and coloured dyes are available.
Properties
Electrical Properties
Hardness & Wear Resistance
Surface Finish
The properties of the hard anodised aluminium as a bearing material are good and are improved by impregnating the coating with lubricants such as “NITUFF®”.
Thermal Properties
Colour
Heat Resistance
Corrosion Resistance
Adhesion
Fatigue Strength
Applications
Hard Anodising is a cost-effective choice for wear and corrosion resistant surfaces on aluminium alloys. Abrasion resistance can be equal to that of tool steel or hard chrome around 1,000 VPN, with the actual hardness of the Hard Anodised film up to 350-500 micro Vickers Hardness. The process is environmentally beneficial due to the chemicals used and its low cost for recycling.
The number of applications for Hard Anodised aluminium continues to grow, and any manufacturer or user of engineering equipment should contact us to discuss whether hard anodic coatings could profitably and advantageously replace existing parts.