关键词: 快速凝固, 表面氧化, 铝合金粉末

Abstract: The structure, the thickness and the composition of the surface oxide layers for the rapidly solidified pure aluminum powder and high-strength Al-7.5Zn-2Mg-2Cu, high-temperature Al-4Mn-4Ni-0.6Mg-0.6Zr, super-light Al-3.2Li-l.lMg-0.3Cu-0.2Zr alloy powders have been studied by using ESCA (Electron Spectroscopy for Chemical Analysis) quantitatively. All the powders exhibit an outer hydrocarbon layer, a surface hydrous oxide layer and an oxide layer. The thickness of oxide layer, which is controlled by the diffusion of oxygen in oxide, is 40 A (consisting of AL2O3) for pure Al powders 35 A (consisting of A12O3) for Al-Mn-Ni-Mg-Zr powders and 37 A(consisting of A12O3 and MgO, A13+ : Mg2+ =1 : 0.06) for Al-Zn-Mg-Cu powders. The oxidation of Al-Li-Mg Cu-Zr powders is controlled by the transoportation of oxygen to the powder surface, which makes the thickness of oxide layer add to 97 A (consisting of A12O3, Li2O and MgO, A13+ : Li + : Mg2+ = 1 : 0.86 : 0.05) for 50-56μm size powders and 117 A(A13+: Li + : Mg2+ = 1 : 1.16:0.09) for 40μm size powders. The effects on the surface of exposure condition have been also studied in the paper.

Key words: rapid solidification, surface oxidation, aluminum alloys powder