采用先包埋、然后化学气相沉积(CVD)的复合工艺，在石墨材料表面制备ZrC涂层，并对其进行氧乙炔焰烧蚀试验。借助X射线衍射(XRD)和扫描电镜(SEM)分析烧蚀前后涂层的微观组织形貌及相组成，研究涂层的抗烧蚀机理。结果表明：包埋-CVD两步法制备的ZrC涂层，包埋层具有双层结构，外层多孔、内层致密；CVD层表面呈凸胞状形貌，为柱状晶结构；包埋多孔层与 CVD 层相互嵌入，形成机械互锁结构，增强了涂层间的界面结合强度。30 s氧乙炔焰烧蚀试验表明：ZrC涂层具有很好的结构稳定性和良好的抗热震性能；烧蚀产物为单斜型ZrO2，质量烧蚀率和线烧蚀率分别为1.50×10-3 g/s和0.47×10-3 mm/s，涂层具有良好的高温抗烧蚀性能和抗冲刷性能。%The ZrC coating was prepared by a two-step technique of pack cementation and chemical vapor deposition (CVD) processes, and investigated by oxyacetylene torch flame test. The surface morphology and phase composition of the coating before and after ablation were studied by SEM and XRD analysis, and then the ablation mechanisms were investigated. The results show that in the as-prepared coating, the coating prepared by pack cementation method has a double structure with the outer porous layer and the inner dense layer;the CVD layer forms columnar crystal structure with smooth arch surface;the porous layer and the CVD layer are mutually embedded to form a mechanical interlocking structure, thus enhancing the interface bonding strength between the coatings. The oxyacetylene torch flame test results show that the ZrC coating remains good structural stability after 30 s ablation and shows excellent thermal shock resistance. The ablation product is monoclinic ZrO2;the mass and linear ablation rates of coated sample are 1.50×10-3 g/s and 0.47×10-3 mm/s, respectively, shows good ablation resistance and anti-erosion resistance.
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