Colour Anodising Gold Finish

What is Anodising?

Anodising simply explained

Anodising is an electrolytic process which is mainly used for corrosion resistance, abrasion protection, and insulation from electricity or aesthetic appearances.

Anodising is the successful development and control of a natural oxidation process that occurs when aluminium is exposed to the atmosphere. The basic process is that an electrical current is passed from the anode (positive) to the cathode (negative).  The product going through the anodising process becomes the anode part of the electric circuit. The product (anode) and the cathodes are placed in the anodising tank which contains dissolved chemicals. A layer of hard aluminium oxide is created on the product surface. If a good electrical contact point is required on the product then these areas can be masked or alocromed.

anodising process

The current causes oxygen to be released at the anode which amalgamates with the aluminium to form aluminium oxide which is the anodic film. 5 to 26 microns in depth can be achieved and this is determined by the time spent in the anodising tank.

The anodic film quality is defined by the concentration of the electrolyte, temperature, and, current density used. At this point the anodic film is extremely porous. Colouring of the oxide film can now be carried out using mainly organic dyes prior to the sealing process, Colour Anodisers are able to offer a large range of colours such as  red, silver, burgundy, navy blue, green, black, and blue. When the anodising and colouring processes are completed a hard transparent surface that is integral with base aluminium is formed.