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本工作研究了微量Ｃｅ、Ｎｂ对Ａｌ６６Ｍｎ９Ｔｉ２５金属间化合物显微组织、微裂纹生成及扩展倾向、维氏硬度、压缩性能、断裂特征、变形亚结构的影响。结果表明，添加微量Ｃｅ有显著的促进晶粒枝晶化和第二相弥散化作用，从而使微裂纹生成和扩展以及沿晶开裂受到一定程度的抑制，因而，压缩强度明显提高，压缩塑性也有改善。微量Ｎｂ的加入，显微组织仍保持等轴状晶粒和粗大第二相，压缩性能未能改善。
In this work, the effects of trace amounts of Ce and Nb on the microstructure, microcrack generation and propagation tendency, Vickers hardness, compressive properties, fracture characteristics and deformation substructure of Al66Mn9Ti25 intermetallic compounds were studied. The results show that the addition of a small amount of Ce can obviously promote the dendrite crystallization and the second phase dispersion, so that the formation and propagation of microcracks and the intergranular cracking are suppressed to a certain degree. Therefore, the compressive strength is obviously increased and the compressive plasticity is also improve. Addition of trace Nb, the microstructure still maintains the equiaxed grains and the coarse second phase, the compression performance failed to improve.