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研究了微量镧、铈、铌、钇对Ａｌ６６Ｍｎ９Ｔｉ２５金属间化合物显微组织、微裂纹生成及扩展倾向、压缩性能、微观断裂和形变行为的影响。研究表明，添加微量元素后，保持Ｌ１２结构，且晶格常数基本无变化，位错可动性得到不同程度的增强。镧、铈有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，因之，压缩强度提高，压缩塑性也有改善。加入微量铌和钇显微组织仍为等轴状晶粒和粗大第二相，压缩性能未能改善。
The effects of trace amounts of lanthanum, cerium, niobium and yttrium on the microstructure, microcrack formation and expansion tendency, compressive properties, microscopic fracture and deformability of Al66Mn9Ti25 intermetallic compound were studied. The results show that after addition of trace elements, the structure of L12 remains unchanged and the lattice constant is almost unchanged, and the dislocation mobility is enhanced to some extent. Lanthanum and cerium promote grain dendrite and second phase dispersion, so that the formation and propagation of microcracks and crystal cracking by a certain degree of inhibition, therefore, the compressive strength, compression plasticity also improved. Addition of trace amounts of niobium and yttrium microstructure is still equiaxed grains and coarse second phase, the compression performance failed to improve.