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42μm降低至30μm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。 Effect of Zr on the Microstructure and Mechanical Properties of 2E12 Aluminum Alloy in T4 State. The results show that the addition of 0.3% Zr can refine the as-cast microstructure of the alloy and reduce the average grain size from 42μm to about 30μm, and promote the equiaxed grains. During the forging, Zr can restrain the recrystallization , To prevent grain growth, improve the microstructure of 2E12-T4 state, improve the mechanical properties of the alloy, the tensile strength, yield strength, elongation and reduction of area increased by 5.4%, 11.3%, 9.7% and 12.6 %; Strengthening mechanism of the alloy mainly includes grain refinement, grain dispersion strengthening and deformation strengthening.