液相先驱体转化法制备TaC抗烧蚀材料

Preparation of TaC Anti-ablation Materials by Liquid Precursor

报道了一种通过液相先驱体转化制备碳化钽的方法．用XRD分析材料高温处理后的相组成及晶态结构;用SEM观察和表征材料的微观形貌．随树脂含量的增加,碳化钽有机先驱体溶液的固化时间缩短．900℃处理后生成细小Ta2O5晶体;经高温处理后,试样转化成立方相TaC．TaC颗粒分布较均匀且基体碳有一定程度的石墨化．随着处理温度的升高,材料的气孔率降低、致密度增大、基体的石墨化程度增强、石墨碳增多且TaC颗粒粒度也明显增大．TaC颗粒是在高温处理过程中通过液相反应机制生成的,且有“扩散-团聚”现象发生．

Tantalum carbide materials were prepared by liquid precursor conversion, and the phase compositions and the microscopic structures of samples were characterized by XRD and SEM, respectiwlv. Ta2O5 crystals are formed inside samples by 900℃ treatment, and after 1600- 2000℃ high temperature treatment, the samples can almost be converted into tantalum carbide materials whose particles disperse homogeneously throughout the carbon matrix. As temperatures elevates the graphitization degree of matrix increases and the grain size of tantalum carbide obviously enlarges, all of these are in favor of improving the anti-ablation properties of materials.