(1. 大连理工大学 铸造中心，大连 116024；
2. 北京航空材料研究院，北京 100095)
摘 要: 研究Zr元素对2E12铝合金T4态显微组织及力学性能的影响。结果表明：添加质量分数0.3%的Zr元素可以细化合金的铸态组织，使晶粒平均尺寸从42 μm降低至30 μm左右，并促使晶粒等轴化；锻造过程中Zr可以抑制合金的再结晶，防止晶粒长大，改善2E12-T4态的显微组织，提高合金的力学性能，其抗拉强度、屈服强度、伸长率和断面收缩率分别提高5.4%、11.3%、9.7%和12.6%；合金的强化机理主要包括晶粒细化、颗粒弥散强化及形变强化。
关键字: 2E12铝合金；锆；电磁连铸；显微组织；力学性能
2E12 aluminum alloy
（1. Research Center of Foundry Engineering, Dalian University of Technology, Dalian 116024, China;
2. Beijing Institute of Aeronautical Materials, Beijing 100095, China）
Abstract: Effects of Zr on microstructures and mechanical properties of 2E12 aluminum alloy were studied. The results show that compared with 2E12 alloy the as-cast microstructures of alloy with 0.3% (mass fraction) Zr can be refined of grain sizes decreasing from 42 μm to 30 μm and characterized with equiaxed grains. Moreover, recrystallization during the forging process can be inhibited. σb, σ0.2, δ and ψ are improved with increasing Zr content, and the improving amplitudes reach 5.4%, 11.3%, 9.7% and 12.6%, respectively. Combined with the microstructures of alloys, the strengthening mechanism are mainly grain-refine, particles dispersion strengthening and improvement of deformation strengthening.
Key words: 2E12 aluminum alloy; Zr; electromagnetic continuous casting; microstructure; mechanical properties
