Process for preparing modified oxide ceramic coatings on barrier-layer metals and products obtained.

摘要

In order to enhance the thickness and wear resistance of oxide-ceramic coatings on barrier-layer metals, a plasmachemical anodic oxidation in a chloride-free electrolyte bath is carried out at a pH from 2 to 8 and constant bath temperature, using a constant current density of at least 1 A/dm<2>, until the voltage settles at a final value. Thus it is possible to generate, on objects made of aluminium or aluminium alloys, an oxide-ceramic coating which consists of corundum, and even on magnesium or titanium, coating thicknesses of up to 150 mu m are achieved.