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采用透射电镜微观分析技术（ＴＥＭ），研究２０９０铝锂合金１９０℃时效若干时间的试样中，片状Ｔ１相与球状β＇相间的交互作用．结桌表明乃相不能切割β＇相，另外Ｔ１相总是以其共格宽面与β＇相相接角；本文分析认为β＇相外位错环的扭结是其上产生Ｔ１相晶核的机制之一；由经典形核理论出发，推导了小平面片状晶核的临界形核功，表明Ｔ１相以β＇相为基底的形核有降低形核功的作用．
Transmission Electron Microscopy (TEM) was used to study the interaction between T1 phase and spherical β ’phase in 2090 Al-Li alloy aged at 190 ℃ for some time. The results show that the phase can not be cut β ’phase, the other phase T1 is always with its wide lattice and β’ phase angle of contact; this analysis that β ’extra-phase dislocation ring kink is the generation of T1 phase nuclei . Based on the classical nucleation theory, the critical nucleation energy of facet-like lamellar nuclei is deduced, which indicates that the nucleation of β phase on T1 phase has the effect of reducing nucleation.