| abstract |
An advantageous method for treating the surface of a metallic substrate made of aluminum or an aluminum alloy, comprising the following steps: providing a water-based mixture with a sol, comprising alkoxy silanes of general chemical formula Si(OR) 4 and organoalkoxy silanes of general chemical formula R″Si(OR′) 3 , in which R and R′ are linear or branched, short-chained hydrocarbon groups with at least one hydroxyl group and R″ is an organic group with a glycidoxy-, merkapto-, amino-, methacryl-, allyl- and/or vinyl-group, applying the mixture to the surface of the metallic substrate and at least in sections, hardening the mixture with a formation of a sol-gel coating connected to the metallic substate. |