用透射电子显微镜就位观察了镍钛合金的马氏体相变和预马氏体相变。发现存在反向记忆的变态单元,它形成的过程可以分为三个阶段: (1)用应变时效相Ni_4Ti_3和位错线来标志和划定单元的界线; (2)弯折分布的R相构成变态单元的界墙; (3)单变态的马氏体充填变态单元的领域。同时对相变晶体学作了讨论。 The martensitic transformation and the pre-martensitic transformation of the nitinol alloy were observed with a transmission electron microscope. It is found that the metamorphic unit with inverted memory exists in three stages: (1) the boundaries of units are marked and delimited by the strained time-dependent Ni_4Ti_3 and dislocation lines; (2) the R phase Constitute the metamorphic cell boundary wall; (3) the metamorphic martensitic filling metamorphic cell field. At the same time, the phase transition crystallography is discussed.