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Cf/Zr C-Si C超高温陶瓷基复合材料利用碳纤维的增韧、Zr C的高熔点、高硬度、优异的耐超高温性能以及Si C-Zr C复合基体良好的抗氧化特性成为了超高温材料中的研究热点。对基体Zr:Si(质量)分别为2:1、4:1、8:1、16:1的带有Si C涂层的Cf/Zr C-Si C超高温陶瓷基复合材料进行2700 K、600 s等离子风洞氧化烧蚀考核试验,评估基体组分配比对材料抗烧蚀性能的影响规律,利用SEM和EDS等分析手段,考察了基体组分配比对烧蚀层微观结构的影响。结果表明,2700 K下,烧蚀中心区表面的Si C快速氧化消耗,基体开始发生氧化烧蚀;基体中Zr的含量越高,试样抗氧化烧蚀性能越好。烧蚀影响层较厚,达毫米级。随着Si含量增加,表层以内生成的Si O2增多,其本身易挥发,烧蚀层孔隙增多,氧气更容易进入内部,烧蚀越严重。随着Si含量增加,Zr C氧化生成的致密Zr O2减少,对碳纤维的保护减弱,碳纤维烧蚀越严重。
Cf / Zr C-Si C ultra-high temperature ceramic matrix composites using carbon fiber toughening, Zr C high melting point, high hardness, excellent ultra-high temperature performance and Si C-Zr C composite matrix good antioxidant properties become super High temperature materials in the research hot spots. The Cf / Zr C-Si C ultra-high temperature ceramic matrix composites with Si C coating with Zr: Si (mass) of 2: 1, 4: 1, 8: 1 and 16: 1, respectively, 600 s plasma wind tunnel oxidation ablation assessment test to assess the influence of the matrix composition ratio on the ablation resistance of the material, the use of SEM and EDS and other analytical means to investigate the matrix group ratio on the ablation layer microstructure. The results show that at 2700 K, Si C on the surface of the ablation center is rapidly oxidized and the matrix begins to oxidize and ablate. The higher the content of Zr in the matrix, the better the anti-oxidation ablation performance. Ablation affected layer thick, up to millimeter. With the increase of Si content, Si O2 generated in the surface layer increases, which itself is easy to volatilize, porosity of the ablation layer increases, and oxygen more easily enters the interior, resulting in more severe ablation. With the increase of Si content, the compact ZrO2 generated by the oxidation of ZrC decreases, the protection of carbon fibers decreases, and the more severe the carbon fiber ablation.