Anodised aluminium components are protected against wear and corrosion, exhibit better sliding behaviour, and look more refined.
Anodising aluminium involves converting the top layer of an aluminium component into a robust oxide layer through anodic oxidation.
BWB uses special systems to anodise aluminium components for aviation, mechanical engineering, medical technology, product design and architecture.
Dimensionally accurate anodising for precision mechanics
Dimensionally accurate anodising involves removing exactly the same amount of material as is deposited in the anodised coating prior to anodising. Tolerances of +/- 3 µm are permitted.
Where necessary, BWB guarantees dimensional accuracy through logged tests and measurements before, during and after anodisation.
Hard-anodising for additional durability
Hard-anodising can achieve particularly hard, durable surfaces. Unlike normal anodising, it involves working with very high currents and temperatures of around 0°C. This can produce a Vickers hardness of up to 550 HV.
Hard-anodised parts may be impregnated with PTFE to further improve sliding properties.
Anodising large and heavy parts for industry and architecture
BWB Oberflächentechnik anodises parts weighing up to 2 tonnes, and measuring up to 22 m in length, 2.2 m in height, and 1.3 m in width.
Surface refinement for designs
Aluminium parts may be colour-anodised for design applications. The palette for anodising colours ranges from black to gold to vivid colours such as red and blue.
Rounding off BWB Oberflächentechnik's surface treatments are additional pre and post-treatments including chemical glossing, sanding, brushing, Pralox refining, decorative blasting and partial anodising (masking).
Colour chart for architecture
Colour chart for industry
| Layer thickness and
| Max. application
| Increase in surface
roughness Ra (µm)*
(h as per ISO 9227)*
| Breakdown voltage
| bis 1000
*Depending on the alloying of the base material. The BWB laboratory calculates the individual values by conducting corrosion and hardness tests, and further expert reports are compiled through the use of microscopy and material analysis.
In addition to pure aluminium (EN AW-1050A), various alloys are also highly suitable for technical and decorative anodisation, such as EN AW-5005, EN AW-5083, EN AW-5754, EN AW-6060, EN AW-6061 and EN AW-6082. High-strength alloys for structural components (e.g. EN AW-7075) are suitable for technical surface coatings.
Table of aluminium-alloy suitability for anodic oxidation
- Chromating (Alodine 1200 yellow and Alodine 1500 transparent)
- Chromiting (RoHS-compliant) Surtec 650, Alodine 160 yellow and Alodine 400 transparent
- Bilatal anodising
- Partial covering/masking
- Aluminium pickling-passivation
- Ematal-coating / Hard ematal-coating