Anodically oxidised and electrolytically coloured casting of a titanium-containing AlMg casting alloy

摘要

Castings of AlMg alloys with Ti contents of up to 0.20% by weight frequently have, after the anodisation and electrolytic colouring in electrolytes containing metal ions, clearly visible defects in the coloured oxide layer. Uniformly dark colour shades cannot be produced. In a casting of a titanium-containing AlMg casting alloy having a fine-grained microstructure, uniform colouring in all desired colour shades from light via bronze to especially black is to be produced by electrolytic colouring by the two-stage process. The titanium content in the casting is between 0.001 and 0.035% by weight and the Mg content is between 1 and 11% by weight. Use for the production of castings having oxide layers, uniformly coloured electrolytically, in dark, in particular brown to black colour shades.