The chemical structure and the surface texture of the basic material have vital signifcance to the galvanising process. They have an effect on adhesion, structure and quality of the surface.

The orderer has got the task to add to an optimal surface result by carefully preparing the workpiece.

A clean-to-bright metal surface is the basic precondition for the final surface result. However, due to its chemical compositon, its fabrication, its treatment or its previous stress each surface is overcast with a thin film extranious or inherent residue.

Among the extranious ones there are oils, greases, metal soaps, dust, old anti-corrosive coatings, residue of production auxiliary agents, etc. Corrosion build-up, developped by oxidation of the material, belongs to the inherent coatings. In the course of pre-treatment of the workpiece, the inherent residues on the surface get totally removed without any problem, as long as corrosion attack is still inconsiderable.

This is not possible quite as problem-free with most of the extranios residues, that can only be dissolved with difficulties or not at all.

Among the extranious layers there are oils and greases. The manufacturer of the wordpiece should try to keep oil and grease away from the surface or make sure that only easily emulsifying oils and greases are applied. If oils and greases remain on the workpiece, surface imperfections may occur.

If during manufacturing oils and greases get changed in cosistancy i. e. by thermal action, the manufacture should consider if they still can be removed by the coater.

The manufacturer of the workpiece is asked to check his manufacturing process to the effect that no substances get into contact with the surface, that disturb or even inhibit the subsequent galvanic coating. Among these substances are i. e. oils that contain silicon.

The manufacturer of the workpiece is further asked to indicate all changes to his manufacturing process that have a bearing on the issues mentioned above.