What is anodising?

Anodising is a specialist electrochemical process that is used to alter the surface of an aluminium substrate with the intention of enhancing its attributes. It is unique in that around 50% of the newly created layer is absorbed into the substrate whilst the other 50% is added on top. This means that the surface is fully integrated with the underlying substrate.

What are the pros and cons of anodising?

There are a number of benefits of using anodising to treat aluminium surfaces, although there are also some minor disadvantages.

Pros

• Anodised surfaces are easy to maintain and clean.
• Anodised surfaces are UV stable and don’t peel or flake.
• The hardness/toughness of the surface is increased, enhancing scratch and wear resistance.
• Corrosion resistance is enhanced, significantly increasing lifespan.
• Anodising boosts aesthetic appeal, and allows for various finishes.
• The process is considered environmentally-friendly.

Cons

• Can only use specific grades of aluminium.
• Cannot be used on stainless steel.
• Can be subject to colour variations.
• Is more expensive than painting or powder coating.
• Requires a specialist skill set.

Industries and applications

Anodised components are used in numerous sectors, including aerospace, automotive, medicine, marine, and electronics.

Examples of items that are often anodised include aeroplane landing gear, car pistons, laptops, cookware, ship fittings, surgical tools/instruments, and industrial rollers.

Surface treatment expertise

If you feel that your business would benefit from using surface treatments, or you would like to know more, specialists such as https://www.poeton.co.uk/surface-treatments/anodising/ can provide advice, and they offer a range of surface treatments such as anodising to suit various requirements.

What does the anodising process involve?

There are three key phases in the anodising process: preparation, anodising, and sealing.

1. Preparation involves cleaning the substrate in order to remove contaminants.
2. Anodising involves submerging the aluminium in an electrolyte bath, passing a current through the bath, and releasing oxygen which reacts with the aluminium and enables the oxide layer to form.
3. The porous oxide layer is then sealed using either chemicals or hot water.