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通过热重量分析法研究了Al/MoSi2 复合材料在 40 0~ 70 0℃的氧化性能 ,采用SEM和X射线衍射仪观察与测定了其表面形貌和相组成。结果表明 :Al/MoSi2 复合材料在 40 0 ,6 0 0和 70 0℃氧化时 ,质量变化较少 ,归因于表面形成较连续的 3Al3 O2 ·2SiO2 保护膜 ;而它在 5 0 0℃氧化过程中 ,大量生成挥发性MoO3 相 ,破坏了 3Al3 O2 ·2SiO2 保护性膜的形成 ,导致了PEST现象的发生。
The oxidation properties of Al / MoSi2 composites at 40 0 ~ 70 0 ℃ were investigated by thermogravimetric analysis. The surface morphology and phase composition of Al / MoSi2 composites were observed and determined by SEM and XRD. The results show that the mass change of the Al / MoSi2 composites is less due to the oxidation of the Al / MoSi2 composites at 40 0, 60 0 and 70 0 ℃, which is attributed to the formation of a more continuous 3Al 3 O 2 · 2SiO 2 film on the surface. During the process, a large amount of volatile MoO3 phase was formed, which destroyed the formation of a protective film of 3Al3O2.2SiO2, leading to the PEST phenomenon.