Characterization of Oxide Growth on Surface of Al-Mg-Si Welded Joint

Abstract

Al-Mg-Si (AA6061) Al alloy plates were joined by the method of gas metal arc welding using Al-5Mg (ER5356) filler metal and were subjected to the oxidation test in flowing air environment at from 8 to 40 hours and the weight gain was measured. The characteristic of oxide grown on welded zone surface was examined by SEM/EDS, XRD, and XPS. Oxide was observed to grow on the fused metal surface suggesting the possibility of modifying the oxide chemistry under high temperature environment. It was found that the oxidation behavior of fused metal affected by the nature of their oxide growth and morphology, was influenced by their welding process and the difference in the chemical composition.