摘要
利用Al-Ti-B体系的放热反应,通过压力辅助放热弥散法(PAXD),原位合成了TiB/TiAl基复合材料。借助XRD,SEM分析了TiB/TiAl复合材料微观组织及并测试了其力学性能,探讨了TiB增强增韧TiAl金属间化合物的机制。研究结果表明:其增强相为TiB,基体相为TiAl和Ti3Al。TiB增强体主要以颗粒状、板状及细棒状均匀分布在基体中,其尺寸范围为亚微米级。复合材料的弯曲强度及断裂韧度较二元的TiAl金属间化合物有很大的提高。原位合成TiB/TiAl复合材料主要强化机制有:弥散强化、热膨胀合理失配强化机制、晶须(晶棒)强化。
In situ exothermic reaction of Al-Ti-B system was adopted to fabricate TiB/TiAl composites by pressure-assisted exothermic dispersion method （PAXD）. The relationship of TiB/TiAl composites of microstructure and properties were analyzed by XRD, SEM and mechanical properties tests. The reinforced mechanism of TiB in TiAl intermetallic was investigated. The results showed TiB was reinforcement phase, TiAl and Ti3Al were matrix. The reinforcing phase TiB with particle shape, plate shape and needle shape was distributed in the TiAl matrix uniformly, and the size of TiB was within sub-micron scope. As to the binary TiAl intermetallic, the bending strength and fracture toughness of TiB/TiAl composites improved effectively. The main mechanism of the in-situ composite TiB/ TiAl1 was dispersion reinforcing, thermal expansion rational mismatch reinforcing, whisker （crystal-bar） reinforcing.
出处
《航空材料学报》
EI
CAS
CSCD
北大核心
2009年第4期90-93,共4页
Journal of Aeronautical Materials
基金
国家自然科学基金资助(50672056)
