本文利用会聚束电子衍射、常规电子显微术及X射线能谱分析,对2024高强铝合金中棒状弥散相Al_(20)Cu_2Mn_3的显微结构进行了研究,测定出该相的空间群为Bbmm,点阵参数为a=2.419nm,b=1.251nm,c=0.786nm,并发现T相易形成多重孪晶,孪生面为{101},多重孪晶〈010〉取向的电子衍射图呈现十次对称性。 In this paper, the microstructure of the rod-shaped dispersion Al 20 Cu 2 Mn 3 in 2024 high-strength aluminum alloy was studied by means of convergent-beam electron diffraction, conventional electron microscopy and X-ray energy dispersive spectroscopy. The space group of this phase was determined to be Bbmm , The lattice parameters of a = 2.419nm, b = 1.251nm, c = 0.786nm, and found that T phase easy to form multiple twins, the twin surface {101}, multiple twin <010> orientation of the electron diffraction pattern showed ten Symmetry.