Electrolytic oxidation – also known as anodising – is an electrochemical process: the surface of the aluminium is converted into aluminium oxide. This oxide layer is solidly attached to the base material; to use a metaphor, it "gets under its skin". An accurate topographical copy of the original structure is created, and the surface retains its metallic looks. Anodised surfaces are practical from an ecological viewpoint, since they can be recycled without any restrictions. The additional benefits of anodising are compelling: the treated surfaces are protected against chemical and mechanical influences. In terms of looks, the broad palette of colour tones on offer proves particularly exciting for architects, designers and even artists.

The BWB Group carries out a very wide range of anodising procedures on components, in order to satisfy a variety of different requirements for decoration, function and corrosion protection.

• Anodising / Electrolytic oxidation
• Hard anodising / Hard electrolytic oxidation
• Chromic acid anodising
• Ematal anodising
• Hard ematal anodising
• Bilatal anodising
• Dyeing
• Electrochemical polishing

Chemical surface conversions

Chemical conversion layers form through treatments in aqueous solutions containing chromic acid or free of chromic acid (RoHS-compliant). The conversion layers are very thin and cause no, or only minimal, changes in dimensions. According to the process selected, the chemical layers are transparent to yellowish in colour – they offer an outstanding key for organic coatings on the metal surface.

Various chemical conversions are available.

• Cromating
• RoHS-compliant chromating
• Acid passivation
• Phosphating
• Black pickling