【摘要】 采用自蔓延高温合成技术制备了 Ti Al/ Al2 O3复合材料 ,研究了原料配比对合成过程及产物特征的影响 ,结果表明 ,随着 Al2 O3含量的增加 ,燃烧温度和燃烧速度均增大 ,材料的致密度得到改善。 Al2 O3颗粒尺寸小于 1μm ,分布于基体交界处 ,有一定程度的团聚。通过差热分析研究了 Al- Ti- Ti O2 体系反应过程 ,发现 Al- Ti O2 还原较晚开始 ,但由于激活能低而速度较快 ,因此较早完成。Ti Al3最早生成 ,但只作为中间产物存在 ,随后向 Ti Al和 Ti3Al相转变的过程为控制环节 ,其激活能也体现为总反应的激活能更多还原

【Abstract】 TiAl/Al 2O 3 composites were synthesized by SHS method The effects of Al 2O 3 content on the SHS process of Al Ti TiO 2 system and the microstructure of products were studied It is shown that both the combustion temperature and wave velocity increase with increasing Al 2O 3 content In addition, the relative density of productsis also improved with more Al 2O 3 content The reaction process of Al Ti TiO 2 system was investigated through thermal differential analysis (DTA) It is concluded that, despite later commencement, the reduction of TiO 2 is completed earlier than reactions between Al and Ti due to faster reaction rate resulted from smaller activation energy TiAl 3 formed in early stage as intermediate product and its conversion to TiAl and Ti 3Al is dominating reaction in Al Ti TiO 2 system更多还原