Hard anodising is a specialised form of anodising that produces a much thicker, harder oxide layer on metal surfaces. This process is typically used when extreme wear resistance, corrosion protection, and durability are required.
How Hard Anodising Works
Hard anodising involves immersing aluminium in a chilled acid electrolyte while passing a controlled electrical current through the metal. The process forms a dense, hard oxide layer that can be several times thicker than that produced by standard decorative anodising.
The low-temperature and high voltage help create a coating that’s extremely hard and wear-resistant, and suitable for heavy-duty applications.
Applications of Hard Anodising
Hard anodising, such as the services offered by firms like https://www.poeton.co.uk/surface-treatments/anodising/hard-anodising, is widely used in aerospace components, automotive parts, industrial machinery, and military equipment.
It’s ideal for items subjected to heavy friction, impact, or chemical exposure, such as pistons, cylinder heads, molds, and sliding or rotating parts, and is also commonly used in hydraulic systems, tooling, valves, and precision engineering components where long-term wear resistance is critical.
Advantages of Hard Anodising
The primary benefit of hard anodising is its exceptional surface hardness, often exceeding 60 Rockwell C, which protects components from abrasion, scratches, and mechanical wear. It also provides excellent corrosion resistance, making it ideal for harsh environments.
Additionally, the coating is integrated with the metal, meaning it won’t peel, chip, or flake, and it can be dyed or sealed for visual appeal or additional chemical protection.
By increasing component lifespan and reducing maintenance, hard anodising provides a cost-effective solution for industries requiring high-performance, durable metal surfaces.