【作者】 郝寅雷；

【导师】 翁志成； 赵文兴；

【作者基本信息】 中国科学院长春光学精密机械与物理研究所 ， 光学， 2001， 博士

【摘要】 反应烧结碳化硅（RSSiC）具有热变形量低、比刚度高和尺寸稳定性高等优良特性，特别适合于空间光学系统的应用，是一种具有广阔应用前景的反射镜材料。因此，碳化硅反射镜的制备技术成为近几年光学工程领域的研究者们关注的焦点之一。 本项目主要包括以下三方面的研究工作：（1）反射镜素坯的制备；（2）反应烧结；和（3）RSSiC性能的表征。 第一部分的研究工作以反射镜素坯的成型和碳化为重点。一方面为降低素坯成型过程的收缩率，我们设计了使用非均相结合剂的凝胶注模成型工艺，另一方面，我们设计了液相渗碳工艺，在此工艺中使用溶胶-凝胶法制备的有机/无机杂化材料前驱体为浸渗剂。此后制备了φ150轻量化反射镜素坯，对上述工艺的可行性进行了实验验证。 第二部分主要描述了反应烧结过程和反应烧结碳化硅显微结构的形成过程，并且借助Si-C系统相图对反应烧结机理进行了理论探索。 第三部分对实验制备的反应烧结碳化硅样品进行了物相鉴定和显微结构观察，并对它的一些重要性能进行了分析和测试。 研究结果表明：（1）通过调节结合剂在陶瓷素坯中的分布可以实现素坯成型“零收缩”的设想，基于这种设想可以制备大尺寸、复杂形状的陶瓷素坯，为RSSiC反射镜的成型提供了一条思路；（2）所设计的液相渗碳工艺可以保证碳在陶瓷素坯中的均匀分布；（3）对反应烧结机理的理论研究表明该烧结过程为溶解-沉淀型。 本工作系首次在国内开展的关于碳化硅质反射镜制备技术的研究工作。更多还原

【Abstract】 Reaction sintered silicon carbide (RSS1C) has low thermal distortion, high specific stiffness and excellent dimensional stability, which make it a promissing mirror material, especially for applications such as space-borne optical systems. Accordingly, silicon carbide mirror manufacturing technology has been a focus of attention in optical engineering. Investigation in this program was concentrated on three main parts: (1) mirror greenbody fabricating, (2) reaction sintering. and (3) material properties characterizing. I In the first part. geeenbody molding and carbonizing are stressed. A gelcasting process was devised with non-uniform-phase adhesive being used to decrease greenbody shrinkage. On the other hand, a liquid-phase geeenbody carbonizing process was contrived using inorganic/organic hybrid precursor prepared by sd-gel technology as infiltrant. In addition, a (1) 150 lightweight mirror model has been fabricated to test the feasibility of these process experimentally. 1n the second part, RSSIC sintering process and its microstructure evolution were described, and theoretical investigation on sintering mechanism by means of Si-C phase diagram was conducted. U In the last part. for RSSiC sample prepared in our Laboratory, phases identification and microstructural observation were performed, and besides, properties analysis and characterizing ware carried out. Result shows: (1) The idea of 搉on shrinkage?molding can be realized by regulating adhesive distribution in greenbody. RSSiC greenbody with large dimension and complex shape can be fabricated by the process base an this idea, which suggest a potential solution for RSSiC lightweight mirror manufacturing; (2) Uniform carbon distribution in greenbody can be achieved by liquid-phase carbonizing process; (3) Analysis of reaction sintering process by means of Si-C phase diagram gives another proof of solution-precipitation theory. This is the first researching program on reaction sintered silicon carbide mirror manufacturing technology in China.更多还原