Anodising

Transform your raw aluminium into a durable, vibrant product with Moss Metal Finishing’s expert anodising services.

What is Anodising?

Anodising is an electrochemical process that creates a hard, corrosion-resistant oxide layer on the surface of aluminium. This layer not only protects the metal from wear and tear but also allows for stunning customization through dyeing.

Moss Metal Finishing offers two types of anodising:

Standard Sulphuric Acid Anodising: This is the most popular choice for decorative purposes. It provides a clear finish that readily accepts dyes, creating a vast array of vibrant colours.

Hard Anodising: This process creates a thicker, tougher oxide layer, making it ideal for applications requiring superior abrasion and corrosion resistance. While less suitable for vibrant colours, it offers a uniform darker appearance.

Thickness and Growth:

Anodising adds to thickness to aluminium with standard anodising adding 5-25µm and Hard Anodising adding 25-80µm. This thickness grows inwards as well as outwards so with a thickness of 10µm – 5µm would be inside the aluminium and 5µm on the outside. Masking can be applied where tight tolerances are required and a handy visual guide to the way anodising growth works can be found on our data sheet page

Benefits of Anodising:

• Enhanced Durability: Anodising increases aluminium’s hardness and scratch resistance, ideal for wear and tear prone applications
• Superior Corrosion Protection: Anodised Aluminium withstands harsh environments, making it perfect for marine and outdoor environments
• Stunning Aesthetics: Achieve vibrant, long lasting colours or a sleek matte finish. Anodising unlocks a world of design possibilities.

Adding Colour to Your Aluminium:

The porous nature of the anodised oxide layer allows for deep dye penetration, resulting in rich, long-lasting colours. Moss Metal Finishing’s skilled technicians can achieve countless shades with precise control over the dyeing process.

If you require a specific colour match contact us today to discuss.

Choosing the Right Alloy:

Not all aluminium alloys are created equal when it comes to anodising. Moss Metal Finishing’s guide outlines the suitability of different grades for both decorative and hard anodising:

1000 (Pure)

The purest grade of alloy and as such anodises very well and can be coloured with excellent results.

2000 (Copper)

Whilst this grade of alloy can be anodised it is generally poor for decorative purposes where a good colour finish is required as it anodises to a dark finish. It is prone to pitting when anodised which also makes it unsuitable for decorative purposes. We can Hard anodise onto 2000 series although due to the copper content it can be prone to burning so we wouldn’t recommend it.

3000 (Manganese)

Due to the high manganese content in this grade of alloy it is very difficult to achieve consistency in the shade of anodising so it is not recommended for colour anodising but is suitable for natural anodising where parts aren’t required to colour match.

4000 (Silicon)

This grade of alloy is well suited to natural anodising but has a dark grey shade when anodised which makes it unsuitable for coloured anodising.

5000 (Magnesium)

This alloy is very good for decorative anodising as most grades take colour very well and it is excellent for Hard anodising

6000 (Magnesium & Silicon)

This is the most common grade of alloy we come across and anodises very well for both decorative and hard anodising.

7000 (Zinc)

We don’t recommend anodising this grade of alloy as it has mixed results although it can come out very well it is prone to burning when Hard Anodised and can have pitting in either process.

CAST Aluminium

As a general rule cast alloys are not suitable for coloured anodising but can be natural anodised well and Hard anodised well. We find that most customers are unaware of what grade of cast their parts are made from but should you be able to choose, the best grades which can be coloured reasonably well are LM0, LM5 and LM31.

Anodised aluminium becomes non-conductive. If your parts require conductivity, specify contact points for masking prior to anodising.

Internal threads may require masking to maintain critical tolerances due to the increased thickness from anodising.

For harsh environments like marine atmospheres, prioritize hard anodising over decorative finishes for optimal corrosion resistance.

Contact us for a Quote Today!

Remember: This information is intended as a guide and may not be exhaustive. For specific inquiries or complex projects, contact Moss Metal Finishing’s experienced team for personalized advice.