(北京科技大学材料科学与工程学院，北京100083)
摘 要: 分析了原位合成制备的TiB2粒子强化铝基复合材料不同凝固组织中TiB2粒子的分布规律和形貌特征。研究结果表明，TiB2在该复合材料中细化晶粒的作用较弱，但有明显的聚集倾向，其聚集程度与熔炼方式和加热温度有关；经半固液成型处理的组织中TiB2的分布特征未改善；六边形和长条形TiB2可以是同一形态的粒子在空间不同方位的表现，六边形TiB2的侧面为{1(-2)10}面；测定了TiB2粒子的尺寸分布 。
关键字: 原位合成；TiB2粒子强化；铝基复合材料
（Materials Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, P.R.China）
Abstract:Analysis was performed on the cast microstructures of in-situ processed aluminum matrix composites reinforced by TiB2 particles with the emphases on their distribution and morphology. TiB2 particles have no remarkable grain-refining effect, but a strong tendency of agglomeration, which depended on melting methods as well as heating temperatures. No improvement of particle distribution was observed in the thixoformed structure. It is shown that rectangular and hexagonal morphologies of TiB2 can stem from a same plate-like particle in different spatial positions. It was observed that the lateral planes of a plate-like TiB2 particle can be {1(-2)10}. The size distribution of TiB2 was measured with imaging analyzer.
Key words: in situ processing; TiB2 particle reinforcement; aluminum matrix composites
