Metal anodising is an irreversible electrochemical process, also known as anodic oxidation, that creates a protective oxide layer on the metal surface. The aim of the treatment is to protect metals such as aluminium, titanium, zinc and magnesium from wear and exposure to external agents. It is a fundamental process for preventing corrosion and abrasion caused by heavy use.
Anodising gives the treated material hardness and consistency. As well as protecting against corrosion, it provides an excellent base for colours, while ensuring electrical insulation and thermal conductivity.
Anodic oxidation of metals: the three stages
To create the oxide layer that covers the metal surface, the metal must react with oxygen during the electrolytic process. First comes pre-treatment of the material (brushing, degreasing, pickling, satin finishing, neutralising); the next stage is the anodic oxidation itself, which forms a porous, protective layer on the metal; the final stage is finishing, which involves oiling the metal.
At the end of the anodising process, the metal’s properties and physical state change, giving it different characteristics. Its hardness increases, providing genuine long-term thermal insulation. After the anodising process, the metal’s appearance can also be improved by applying a layer of colour.