难熔金属及其化合物与C/C复合材料相互作用研究

利用织物混编难熔金属丝和浸渍含难熔金属化合物酚醛树脂两种方法，并结合常用的沥青浸影炭化工艺制备了含WC、TaC、ZrC、HfC的C／C复合材料，分析了难熔金属组分在工艺过程中的变化及其与C／C复合材料的相互作用。结果表明：混编的难熔金属丝既可以与基体碳也可以与碳纤维发生化学反应，导致部分碳纤维被侵蚀受损；另外，由于线膨胀系数差异大，造成难熔金属丝以及周围部分碳纤维或整束碳纤维的断裂。颗粒状难熔金属化合物不会造成整束碳纤维断裂，颗粒表层基体碳的取向程度明显高于周围树脂碳。

Interaction of Refractory Metals Compounds With Carbon/Carbon Composites

WC, TaC, ZrC and HfC are introduced into carbon/carbon composites by co-woven of carbon fibers with refractory metal filaments, or impregnating of refractory metal oxides dopedphenolic resin, and further densification is finished by commonly used pitch impregnation/carbonization processes. Interaction between carbon and metal compounds is analyzed in detail. The results show that the metal filaments react with both the carbon fibers and matrix carbon and result in partially detriment to carbon fibers. Breaking of both carbon fiber bundles and metal filaments occurs due to thermal mismatch of these two kinds of components during repetitious procedures of temperature changes. Breaking of carbon fibers has never been observed in the case of particle doping with metal oxides. Instead of that, a thick layer of high ordered carbon is formed on the surface of the particles abnormally from phenolic resin, which is regarded as non-graphitized carbon precursor.