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,2273K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[2.029×105(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 composite material is widely used in aerospace field and others, however, it is easy to be oxidized at high temperature.In order to improve the oxidation resistance, ZrC is introduced as an oxidation inhibitor used in matrix modification of C/C composite material. Flat plate samples of ZrC/C composite materials were prepared by hot-pressing sintering. The degree of graphitization increases with rising sintering temperature, and layer structure of carbon matrix is observed clearly in the sample treated at 2273 K. Diffusion behavior of Zr in C matrix at high temperature is studied, which can be generally expressed as D=3.382×10?11 exp[2.029×105/(RT)]. The diffusion of Zr in C matrix leads to the over-saturation of C in the micro area and the oversaturated C precipitates as graphite. This continuous process promotes the transformation of carbon to graphite.