C_f/SiC复合材料表面熔盐反应法锆金属化研究

Study on Zirconium Metallic Coating for C_f/SiC Composites by Molten Salt Reaction

利用熔盐热歧化反应在碳纤维增强碳化硅(Cf/S iC)复合材料表面制备了锆金属化层。研究反应时间对金属化层形貌、物相、厚度的影响,分析S iC/Zr的界面反应机理。结果表明,锆金属化层优先在S iC区域生成,随着反应时间的延长,逐渐在C纤维区域生成,当反应时间达到3h时,金属化层覆盖完全;金属化层主要物相为Zr,Zr3O,ZrC和Zr2S i;金属化层的生成受固相中Zr,S i,C等元素扩散控制。

Zirconium metallic coating was prepared on carbon fibre reinforced silicon carbide（Cf/SiC） composites by molten salt reaction method. The effects of reaction time on the morphology, phase composition and thickness of the metallic coatings on Cf/SiC com- posites were characterized by SEM and XRD. The interface reaction mechanism between SiC and Zr was investigated. The results show that the metallic coating is firstly deposited on the surface of SiC areas. With the increase of reaction time, the coating begins to deposit on carbon fibres. And, the surface of composites is covered by the metallic coating entirely when the reaction time is up to 3 h. The main composition of coating is Zr, Zr3O, ZrC and Zr2Si. The control step for the formation of metallic coating is the diffusion of Zr, Si and C.