Evaluation of the Effect of CO2 Cover Gas on the Rate of Oxidation of an AlMgSi Alloy

Abstract

15 µm. Pure Ar had a positive effect on the oxidation rate lowering the mass gain to 2.80% and a thickness of ~10 µm. A mass gain of only 0.46% and a continuous dense oxide layer of 200–400 nm, with an additional granular discontinuous oxide layer of ~2 µm underneath, was obtained during heating in 4% CO2. This confirms that even in the case of the AlMgSi alloy, small amounts of CO2 have a significant inhibiting effect on the oxidation rate.