ANODIZED ALUMINIUM OF DARK GREY COLOUR Russian patent published in 2020 - IPC C22C21/06 C22F1/47 C25D11/14 

FIELD: chemistry.

SUBSTANCE: invention relates to aluminium alloys, particularly to nonferrous aluminium alloys, and can be used in architecture, as well as for other decorative applications. Aluminium alloy contains up to 0.40 wt. % of Fe, up to 0.25 wt. % of Si, up to 0.2 wt. % of Cr, from 2.0 wt. % to 3.2 wt. % of Mg, from 0.8 wt. % to 1.5 wt. % Mn, up to 0.1 wt. % Cu, up to 0.05 wt. % Zn, up to 0.05 wt. % Ti, and up to 0.15 wt. % impurities, the rest is aluminium, wherein the alloy contains at least 1.5 wt. % intermetallides Al₆Mn and/or Al₁₂(Fe,Mn)₃Si. Method of producing aluminium sheet containing dispersoids includes casting of aluminium alloy, ingot homogenisation, hot rolling of ingot for production of hot-rolled intermediate product, cold rolling, intermediate annealing, cold rolling of intermediate annealing product to produce cold-rolled sheet and annealing of cold-rolled sheet to form aluminium sheet containing dispersoids. Invention is aimed at obtaining aluminium alloys and aluminium sheets from them, having natural dark-grey colour during anodising.

EFFECT: alloys do not require any absorption or electrolytic painting separately from the anodising process to achieve dark-grey colour.

17 cl, 9 dwg, 1 tbl, 4 ex