SiC/Ti基复合材料C/Mo双涂层界面改性机理研究

项目名称： SiC/Ti基复合材料C/Mo双涂层界面改性机理研究

项目编号： No.51201134

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 金属材料学科

项目作者： 罗贤

作者单位： 西北工业大学

项目金额： 25万元

中文摘要： 目前用于增强Ti基复合材料的SiC纤维表面通常带有C涂层，用以保护纤维和缓解界面附近较大的热残余应力。但C涂层易于与基体反应形成脆性反应层，导致界面附近产生较大的热残余应力和反应层在承载过程中易于首先开裂，而且C涂层会不断地被消耗。Mo的界面稳定性优良，而且Mo能使其附近的Ti合金被β化而韧塑性增加。因此，本项目提出在SiC 纤维有C涂层的基础上，再次引入Mo涂层作为界面改性涂层，以进一步改善纤维/基体界面相容性和提高 SiC/Ti 基复合材料力学性能。将系统研究制备态和不同真空热暴露处理后界面微区的组织结构形成规律和机理，分析界面微区组织结构演变对界面力学行为的影响机制；掌握界面反应和元素扩散对复合材料抗拉强度、裂纹扩展行为的影响规律，并从纤维、基体和界面等角度揭示其微观本质，为 SiC/Ti基复合材料界面优化设计、延长其高温使用寿命奠定理论基础。

中文关键词： C/Mo双涂层；界面改性；力学性能；SiC/Ti6Al4V复合材料；SiC/TiAl复合材料

英文摘要： The surface of SiC fiber used as reinforcement of Ti-matrix composites usually has C coating currently, which is used to protect the fiber and slow down the thermal residual stresses. However, C coating is feasible to react with the matrix to form a brittle reaction layer, which leads to great thermal residual stresses around the interface as well as the reaction layer is feasible to crack initially during the loading process, and C coating can be comsumed quickly. Mo has excellent interfacial stability, and it can make its surronding Ti alloy β stabilized to have beter toughness.Therefore, Mo coating will be introduced as interfacial modification layer on the basis of SiC fiber (W core, with a diameter about 100 μm) having C coating in this projiect, which is used to improve the fiber/matrix interfacial compatibility and the mechanical properties of SiC/Ti composites. The formation rule and mechanism of the interfacial zone in the SiC/Ti composites with C/Mo duplex coating after fabrication and thermal exposure in vacuum will be studied systematically, and the effct of interfacial microstructure evolution on the interfacial mechanical behavior (such as interfacial bonding strength, interfacial debonding failure mode and the distributions of thermal residual stresses in the interfacial zone) will be analyzed. Fu

英文关键词： C/Mo duplex coating；interfacial modification；mechanical properties；SiC/Ti6Al4V composite；SiC/TiAl composite