合金反应熔渗法制备C/C-HfC复合材料微观结构及抗烧蚀性能

Microstructure and Ablation Resistance of C/C-HfC Composite Prepared by Alloyed Reactive Melt Infiltration

发展了一种Hf C改性C/C复合材料的快速低成本合金反应熔渗制备技术,采用反应熔渗铪基合金制备了性能优异的C/C-Hf C复合材料。XRD分析表明C/C-Hf C复合材料由C、Hf C、Zr C和Si C相组成。合金反应熔渗过程中,合金熔体与热解碳反应形成了层状的基体显微组织。采用激光烧蚀法测试了C/C-Hf C复合材料的抗烧蚀性能,烧蚀60 s后C/C-Hf C复合材料的线烧蚀率为0.008 mm/s,明显低于C/C复合材料预制体的线烧蚀率0.024 mm/s。激光烧蚀后复合材料烧蚀表面形成了一层Ta2O5和Hf O2相组成的抗烧蚀层,有效减小了C/C-Hf C复合材料进一步的烧蚀破坏,大大提高了C/C-Hf C复合材料的抗烧蚀性能。

A high performance and low cost Hf C modified C/C composite(C/C-Hf C) is prepared by hafnium based alloyed melt in ltration. A layed microstructure is formed due to the reaction of pyrolytic carbon with the infiltrated hafnium based alloy. XRD analysis indicates that the as-produced C/C-Hf C composite is composed of carbon, Hf C, Zr C and Si C phases. A laser beam is used to test the ablation resistance of the C/C-Hf C composite. After ablation for 60 s, the linear ablation rate of the C/C-Hf C composite is 0.0008 mm/s, which is much smaller than that of C/C composite preform, 0.024 mm/s. An ablation resistant layer composed of Ta2O5 and Hf O2 is formed on the ablated surface, which effectively prevent the C/C-Hf C composite from subsequent ablation and thus, the ablation resistance of the C/C-Hf C composite is greatly improved.