【摘 要】
：
采用前驱体转化法制备了致密性良好,力学性能优异的Cf/ZrB2-SiC超高温陶瓷基复合材料.采用小发动机及电弧风洞分别对材料的烧蚀性能进行了研究,采用扫描电镜和X射线衍射分析烧蚀后材料的微观结构及物相变化.结果表明:复合材料在小发动机高、低两种不同状态烧蚀后,表面无明显烧蚀,结构保持完整;在电弧风洞平板烧蚀实验中,热流密度为2MW/m2,材料表面最高温度达到2000℃,材料的平均线烧蚀速率为0.0
【机 构】
：
先进功能复合材料技术重点实验室 北京100762 空间物理重点实验室 北京100076
论文部分内容阅读
采用前驱体转化法制备了致密性良好,力学性能优异的Cf/ZrB2-SiC超高温陶瓷基复合材料.采用小发动机及电弧风洞分别对材料的烧蚀性能进行了研究,采用扫描电镜和X射线衍射分析烧蚀后材料的微观结构及物相变化.结果表明:复合材料在小发动机高、低两种不同状态烧蚀后,表面无明显烧蚀,结构保持完整;在电弧风洞平板烧蚀实验中,热流密度为2MW/m2,材料表面最高温度达到2000℃,材料的平均线烧蚀速率为0.0008mm/s,平均质量烧蚀率为0.00222g/s.材料表现出了良好的抗烧蚀性能.通过对烧蚀后材料微观结构分析,烧蚀过程中材料表面形成一层致密的Si02氧化膜,能够保护环境中的氧向材料内部扩散,保护基体材料,同时ZrB2在烧蚀过程中生成高熔点Zr02,能够保证材料结构完整,起到抗烧蚀的作用.文章探讨了ZrB2组元的加入对复合材料微结构及烧蚀性能的影响机理,研究结果展示了此类材料作为高温结构材料的良好应用前景.
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