由涂刷法制备了四种不同配比的新型炭/炭(C/C)复合材料磷酸盐防氧化涂层,通过研究确定了优化涂层方案,涂覆有该涂层的C/C复合材料试样在700℃下空气中氧化100h后,失重率仅为0.952%,热震实验和浸海水恒温氧化实验证明该涂层仍具有良好的抗氧化性能.涂覆有该涂层的C/C复合材料在600℃～800℃时的Arrhenius曲线由两条折线组成,折点为700℃,在600℃～700℃下的氧化表观活化能为139kJ/mol;700℃～800℃下则为93kJ/mol.%Four phosphate antioxidative coatings with different compositions were prepared using a slurry brushing method, and were characterized by weight loss kinetics, thermal cyclic performance and seawater immersion tests. Changes in the microstructure of the coating before and after oxidation were also characterized using SEM and XRD. Results show that the antioxidative properties of a coating are determined by the self-healing, compactness, adherence, and chemical inertness of the coating, which are all determined by the composition. The weight loss kinetics study under oxidative conditions show that between 600 and 700 ℃, the oxidation is controlled by kinetics with an activation energy of 139kJ/mol. Between 700 and 800℃, the oxidation is controlled by diffusion with an activation energy of 93 kJ/mol.
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