Method for and equipment for suppressing discoloration of Al—Mg products

Abstract

Method and means for suppressing discoloration during thermal treatment of a product of a magnesium containing aluminium alloy, the alloy contains in wt. % Mg: 0.45-12.0, with a preferred range of 0.45-6.0 wt %. The product, being either an extrusion billet, a sheet ingot, a cast product, or a forged product is heated to a temperature T where it is prone to surface discoloration and oxidation, wherein during the thermal treatment it is exposed to a suppressing atmosphere comprising 0.5-5.0% CO2 gas with a preference for 0.5-1.5% CO2 gas.

Dependencies are inferred from the claim text.