【摘要】 通过扫描电镜（SEM）、透射电镜（TEM）和万能拉伸试验机等研究了不同Sc含量（0、0.1和0.2 mass%）对Al-3.2Cu-1.5Li合金微观组织及力学性能的影响。结果表明：适量Sc的添加可以细化合金晶粒，添加0.2 mass%Sc的合金晶粒细化效果较为明显，热轧态和T6态合金的组织以亚结构特征为主，沿位错或亚晶界析出的细小、稳定的Al₃（Sc, Zr）/Al₃（Li, Sc, Zr）弥散相能够有效抑制再结晶。随着Sc含量的增加，合金的抗拉强度逐渐降低，伸长率先增加后降低，当Sc含量为0.1 mass%时，合金的力学性能较好，抗拉强度和伸长率分别为480.4 MPa和13.0%。更多还原

【Abstract】 Effect of different Sc contents（0 mass%, 0.1 mass% and 0.2 mass%） on microstructure and mechanical properties of Al-3.2Cu-1.5Li alloy was studied using scanning electron microscopy（SEM）, transmission electron microscopy（TEM） and universal tensile testing machine.The results show that the addition of an appropriate amount of Sc can refine the alloy grains, and the addition of 0.2 mass% Sc has a more significant effect on grain refinement.The microstructure of hot-rolled and T6 state alloys is mainly dominated by substructure, and the fine and stable Al₃（Sc, Zr）/Al₃（Li, Sc, Zr） dispersed phases precipitated along dislocations or subgrain boundaries can effectively inhibit recrystallization of the alloy.With the increase of Sc content, the tensile strength of the alloy gradually decreases, and the elongation first increases and then decreases.When the Sc content is 0.1 mass%, the mechanical properties of the alloy are better, with tensile strength and elongation of 480.4 MPa and 13.0%, respectively.更多还原