中文摘要：

本文采用电场激活压力辅助燃烧合成工艺（FAPAS）,以Ti-Al和Ni-Ti-C体系的放热反应,实现了TiC陶瓷颗粒增强的Ni基复合材料的原位合成以及Ti-TiAl-（TiC）pNi功能梯度材料的同步连接制备。借助SEM和XRD等手段分析了各层界面的相组成和微观结构以及界面元素扩散特征,探讨了电场对功能梯度材料制备过程中各层间界面的冶金特征及连接结构的影响,揭示了电场作用下,利用放热体系进行原位合成和扩散连接的机制。研究结果表明,外加电场条件下,钛粉和铝粉反应形成TiAl相产生的化学热促进了钛基板与TiAl层界面原子的扩散溶解,是两者形成连接的关键;钛-碳反应热促进TiC/Ni细晶复合结构形成,提高了TiC颗粒与基体之间的润湿性和复合材料层的致密度。

英文摘要：

In-situ synthesis and diffusion bonding of functionally graded material（FGM）Ti-TiAl-（TiC）pNi samples prepared by field-activated pressure-assisted synthesis process（FAPAS）were investigated and the reactions of Ni＋Ti＋C and Ti＋Al were introduced as exothermal reaction systems.The microstructure,phase composition and elements concentration profiles across the interfaces between layers were characterized by scanning electron microscopy（SEM）,X-ray diffractometry（XRD）and other measures.The mechanism of in-situ synthesis and diffusion bonding under electric field were discovered by analyzing the metallurgical process and bonding structures of layers.It is indicated that the reaction between Ti and Al is the key factor for the boding of Ti substrate and TiAl intermetallic compound layer due to the heat produced by the reaction.The reaction of Ti and C facilitates the forming of composite of TiC/Ni with fine structure and increases its densification by improving the wetting ability between Ni and TiC under the action of the field.