【摘要】 本文采用透射电镜系列倾转,选区电子衍射及会聚束电子衍射技术,系统研究了一种Al-Li-Cu-Mg-Zr合金中的显微组织。结果表明,该合金中的主要强化相为δ′相,其生长符合粗化动力学。β′相可作为δ′相的核心,并加快其析出速率;合金中的另一主要强化相为s′相。s′相单体为板条状,许多平行生长的s′相单体拼合在一起形成片状的s′相板条群。s′相单体的惯习面为{210}_α,沿<100>_α方向长大,但s′相的片状板条群却躺在{110}_α面上;T₁′相在时效组织中占的体积分数很小,在该合金中不是主要强化相;长时间时效后在晶界上主要形成T₂相。更多还原

【Abstract】 In this paper, the microstructure of an Al-Li-Cu-Mg-Zr alloy was studied systematically by TEM serial rotation, select area electron diffraction, and convergent beam electron diffraction techniques. The results show that the major strengthening phase in the alloy is δ’ （Al₃Li）, and its coarsening rate with time follows the Lifsitz-Wagner kinetics. β’ （Al₃Zr） can be nuclei of δ’ phase and accelerate its coarsening rate. Another major strengthening phase in the alloy is s’ （Al₂CuMg）.The unit of s’ phase is lath-shaped, and many s’ phase units parallel to each other form a plate-shaped bundle of s’ phase laths. The lath-shaped units of s’ phase have habit planes of {210}_α and grow along <100>_α orientation, but the plate-shaped bundles of s’ phase laths lie on the{110}_α planes. T₁’ phase is of small volume fraction in the microstructure. After aging for long times, equilibrium precipitates form on grain boundaries, most of which are T₂ （Al₆ Cu Li₃） phases.更多还原