2000 Volume 64 Issue 4 Pages 227-233
We investigated the breakaway behavior of the surface oxide film on Al-Si-Mg alloy powder particles by X-ray photoelectron spectroscopy using synchrotron radiation (SR-XPS), which is the topmost surface analysis method with less than 1.5 nm analysis depth and has high sensitivities. During heating the powders up to 823 K, the magnesium dissolved in the powder particles was concentrated to the surface oxide below 670 K, and saturated in the composition with a Mg/Al ratio of about 0.5. Over 670 K, the metallic aluminum appeared on the topmost surface of the particles. We speculated that the surface reaction were due to the reduction of surface oxide film by the concentrated magnesium or the breakaway of the surface oxide film by the crystallization of MgAl2O4.
