碳纤维增强铝基复合材料具有高比强度、高比模量等优异的力学性能，在航空航天领域有着极广泛的应用前景。然而，石墨纤维增强铝基复合材料在使用过程中极易发生多种形式的腐蚀破坏。利用SEM、EDS、全浸泡试验、极化曲线测试等手段，对Grf／6061A1复合材料表面不同成膜时间的稀土转化膜耐蚀性能进行了探讨。结果表明：稀土转化膜成膜完整时能有效阻碍氧和电子的迁移，从而使材料腐蚀电位φcorr上升，腐蚀电流密度icorr显著减小，点蚀敏感性下降，耐蚀性能显著提高；稀土膜成膜不完整时，不能有效阻碍氧和电子的迁移，相反由于成膜过程对材料的腐蚀作用，导致材料耐腐蚀性不佳甚至有所降低。%With the high specific strength and high specific modulus, carbon fibre reinforced aluminum matrix composites has a broad prospect of application in aerospace field. However, several forms of corrosion might happen in the course of use. In this paper, the morphology and composition of Ce conversion coating are studied by the scanning electronic microscope （SEM） and energy disperse spectroscopy （EDS）. The corrosion resistance of the conversion coating is examined by immersion tests, polarization curves and electrochemical impedance spectroscopy. The results show that the complete Ce conversion coating could hinder the transfer of oxygen and electrons. Thereby, the corrosion potential φcorr of the specimens increases and the corrosion current density ieorr decreases. As a result, the sensitivity of pitting corrosion of the specimens reduces and the corrosion resistance increases. Due to the non-complete coating could not hinder the transfer of oxygen and electrons effectively and the corrosion behavior during coating formation, the corrosion resistance of the specimens decreases.
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