What is the purpose of anodising treatment on aluminium?

Anodising treatment on aluminium serves primarily to enhance corrosion resistance. This is achieved by converting the surface of the aluminium into a durable, oxide layer through an electrochemical process. The oxide layer formed during anodising is much thicker than the natural oxide film that forms on untreated aluminium and provides a robust barrier against environmental factors, such as moisture and chemicals, which can lead to metal degradation.

Additionally, the anodised surface can be further enhanced with dyes or pigments, making it suitable for decorative applications while still maintaining the corrosion-resistant properties. This protective layer also helps to ensure that the underlying aluminium does not corrode easily, extending the lifespan of the component or structure made from aluminium.

While anodising does impact other properties, such as improving surface hardness and allowing for painting or dyeing, its primary purpose is to provide excellent corrosion protection, making it a vital treatment in industries where aluminium components are exposed to harsh environments.