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C/C复合材料广泛应用于航空航天等领域,但在高温环境中极易氧化,可以通过基体改性改善其抗氧化性能,而ZrC作为氧化抑制剂应用已取得良好效果。通过高温热压烧结的方法制备了ZrC/C复合材料的平板模型样品;碳基体的石墨化程度随着烧结温度的升高而增加,2273 K烧结的样品中观察到了明显的层状结构;研究了高温下Zr元素在碳基体中的扩散行为,得到Zr元素在碳基体中扩散的一般表达式为D=3.382×10~(-11)×exp[2.029×10~5(RT)]。Zr元素在碳基体中的扩散会导致微观区域内碳的过饱和并析出石墨结构的碳,而Zr元素在扩散中和周围无定形碳生成碳化物再析出碳的过程促进了碳基体的石墨化。
C / C composites are widely used in the fields of aerospace, but they are easily oxidized in high temperature environment, and their anti-oxidation properties can be improved by matrix modification. However, the application of ZrC as an oxidation inhibitor has achieved good results. The flat plate samples of ZrC / C composites were prepared by high temperature hot press sintering. The graphitization degree of the carbon matrix increased with the increase of the sintering temperature. The obvious lamellar structure was observed in the sintered samples of 2273 K. The diffusion of Zr element in carbon matrix at high temperature shows that the general expression of Zr element in carbon matrix is D = 3.382 × 10 ~ (-11) × exp [2.029 × 10 ~ 5 (RT)]. The diffusion of Zr element in the carbon matrix results in the supersaturation of the carbon in the microscopic region and the precipitation of carbon in the graphite structure. The Zr element diffuses into and around the amorphous carbon to form carbide and then the carbon is precipitated, which promotes the graphitization of the carbon matrix .