电场激活原位合成(TiC)_pNi/TiAl/Ti功能梯度材料

In-Situ Synthesis of (TiC)_pNi/TiAl/Ti Functional Gradient Materials via Field-Activated Process

运用电场激活压力辅助合成(FAPAS)和原位合成技术制备了(TiC)pNi/TiAl/Ti功能梯度材料,研究了电场对材料合成及层界面扩散连接的作用。采用光学显微镜、扫描电子显微镜、能谱和X射线衍射仪分析了梯度材料各层及界面微观组织、相组成和元素分布。结果表明,电场的施加以及TiAl的燃烧反应是合成材料的关键;经原位合成的TiC颗粒均匀细小;金属陶瓷层/TiAl/Ti基板的界面区产生了成分的互扩散并形成了良好的冶金结合。钛板到金属陶瓷层的显微硬度呈梯度变化且具有较好的抗热震性。

（TiC）PNi/TiAl/Ti functional gradient materials （FGMs） were prepared by field-activated pressure-assisted synthesis （ FAPAS） and in-situ synthesis processes. The roles of the electric field in material synthesis and diffusion bonding of layers were investigated. The microstructure and phase composition of each layer as well as component distribution of elements across the interfaces of the layers were analyzed by means of OM, SEM, EDS and XRD. The results show that the imposition of the electric field and the combustion reaction of TiAl is the key for the successful synthesis of FGMs; the TiC particles formed by in-situ synthesis process are fine and distributed uniformly; moreover, concentration profiles of elements across the interfaces of the layers show significant inter-diffusion and good metallurgical bonding. The sample has an excellent thermal shock resistance ability and gradient distribution of microhardness across the titanium substrate to the surface layer.