What Is Anodising in Engineering? ISO 10074-2 Standards Explained

24 April 2026

Verified by Rachel Mayfield, Supply Chain Analyst - April 2026

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Anodising is an electrochemical process that forms a protective oxide layer on aluminium, improving corrosion resistance and surface hardness. The process involves immersing the aluminium component in an electrolyte solution and passing an electric current through it to oxidize the metal's surface. This results in a uniform coating of aluminium oxide several microns thick. Anodising is widely used across various industries for its ability to enhance durability, appearance, and resistance properties of aluminium components. Common applications include aerospace parts, architectural elements like window frames and roofing materials, consumer electronics enclosures, and automotive trim pieces. The process also allows for better adhesion of paints and glues while maintaining a smooth surface finish. ISO standards such as ISO 10074-2 and BS EN ISO 3509 provide guidelines for anodised aluminium finishes. Ensuring consistent quality across different manufacturers. These standards specify the minimum thickness of the oxide layer required for various applications based on environmental exposure conditions. For example, a typical hardcoat anodizing process can achieve a surface hardness up to 1800 Vickers and a film thickness ranging from 25-45 microns. When selecting engineering components, engineers often consider anodising as part of their material selection criteria due to its corrosion resistance properties. Anodised aluminium parts don't require regular maintenance like painting or powder coating does, reducing long-term costs and environmental impact. The process also enhances the component's aesthetic appeal by providing a variety of colour options through dyeing processes. In summary, anodising is a versatile surface treatment for aluminium components that provides enhanced durability and improved resistance to corrosion. Engineers should consider this option when specifying materials for applications where these properties are critical. Such as in outdoor structures or marine environments. For instance, the British Institute of Anodying (BIAFD) recommends using Type III hard anodising for high-wear industrial parts due to its superior hardness and wear resistance.

Frequently Asked Questions

What is Anodising?

An electrochemical process that forms a protective oxide layer on aluminium, improving corrosion resistance and surface hardness.

What is the primary purpose of anodising in engineering applications?

Anodising creates a protective oxide layer on aluminium components, enhancing their durability and corrosion resistance. It also improves surface hardness and allows for better adhesion of paints and glues.

Which ISO standards should be considered when choosing an anodised finish for an aluminium component?

Engineers should refer to ISO 10074-2 and BS EN ISO 3509, which provide guidelines on the minimum thickness of the oxide layer required based on environmental exposure conditions. These standards ensure consistent quality across different manufacturers.

How does one choose between hardcoat anodising and other types of anodised finishes?

Hardcoat anodising is preferred for applications requiring high surface hardness up to 1800 Vickers, with a film thickness ranging from 25-45 microns. Other variants like sulphuric acid anodising offer thinner coatings but are suitable for aesthetic purposes and improved paint adhesion.

Are there any UK suppliers recommended for anodised aluminium components?

While mlc.org.uk doesn't provide specific supplier lists, engineers can search for ISO-certified UK manufacturers known to comply with standards like ISO 10074-2. These companies offer reliable anodising services tailored to various engineering needs.

What factors influence the cost and availability of anodised aluminium products in the UK?

The cost and availability of anodised aluminium components depend on the type of anodising process chosen, the quantity required, and environmental exposure conditions. Hardcoat anodising tends to be more expensive due to its higher durability requirements but is widely available from certified UK suppliers.

What is anodising and why is it important for aluminium components?

Anodising is an electrochemical process that transforms the surface of aluminium into a durable, corrosion-resistant oxide layer. It's important because it enhances durability and appearance while improving resistance properties, making it suitable for various applications such as aerospace parts and architectural elements.

What are some common types or variants of anodising used in engineering?

Common types include hardcoat anodising which can achieve a surface hardness up to 1800 Vickers with film thickness ranging from 25-45 microns. Another variant is Type II sulphuric acid anodising, often used for improved corrosion resistance and wear resistance.

How should engineers choose between different types of anodised finishes based on ISO standards?

Engineers should refer to ISO standards such as ISO 10074-2 and BS EN ISO 3509 which specify minimum thickness requirements for the oxide layer depending on environmental exposure conditions. These guidelines help in selecting appropriate anodising processes that meet durability criteria for specific applications.

Where can UK engineers find reliable suppliers of anodised components, and what factors should they consider regarding cost and availability?

UK engineers can find reliable suppliers through industry networks or by consulting directories like the MLC (Machine Learning Company) website. When considering cost and availability, factors such as batch size, lead times, quality certifications under ISO standards, and surface preparation methods should be evaluated to ensure efficient procurement processes.