随着航空航天领域对大型轻量化构件的需求日益增加，研发新型Al-Li合金制备技术能够提升制造效率，减轻构件重量。本工作采用一种Al-Cu合金丝材与Al-Li二元合金粉末同步输送的电弧增材制造方法，成功制备了Al-Cu-Li合金试样。利用OM、SEM、XRD、TEM和Vickers硬度仪对试样的晶粒形貌、物相组成进行表征并测量硬度。结果表明，电弧增材制造Al-Cu-Li合金沉积态试样由10~20 μm的细小等轴晶组成，且晶界处存在半连续网状共晶θ (Al₂Cu)相。增材制造热循环作用还会导致晶界附近析出T_B (Al₇Cu₄Li)相与T₁ (Al₂CuLi)相。T₁相主要分布于试样的中部及底部，且随着增材制造热循环次数的增加T₁相含量呈上升趋势，试样底部的T₁相含量最高。电弧增材制造Al-Cu-Li合金沉积态试样的最大硬度为126.7 HV_0.1，略高于其他电弧增材制造2219 Al-Cu合金，这主要得益于细小的等轴晶组织以及热循环的作用下所产生的T₁相。

Al-Li alloy has become an optional material for load-bearing components in aerospace because of its low density, high specific strength, and good fatigue performance. Currently, the widely used casting process to fabricate large Al-Li alloy structural parts has the issues of active and highly toxic Li elements, high equipment cost, long production cycle, limited forming size, and low material utilization. Wire and arc additive manufacturing technology uses an arc heat source to melt the raw materials, mostly prealloyed wires, and directly deposits the materials layer-by-layer by controlling the required components using a computer. It has the technical advantages of a short processing cycle, high material utilization, and a large frame formation, providing a new possibility for forming large Al-Li alloy components. Currently, the prealloyed welding wire is usually used as a raw material for arc additive manufacturing, but it is challenging to make high-performance Al-Li alloy wire and Li is strongly ablated under a high-temperature heat source. In situ metallurgy with an arc melt pool has prepared Al-Li alloys with good internal quality and superior performance potential while reducing manufacturing costs. Therefore, exploring the controllable addition of Li elements during the deposition process is necessary. Herein, the Al-Cu-Li alloy sample was successfully fabricated using a multimaterial arc melting deposition technology combining Al-Li alloy powder and 2219 Al-Cu alloy wire. The grain morphology, phase composition, and hardness of the as-built alloy sample were further analyzed. The as-built Al-Cu-Li alloy sample comprises fine equiaxed grains of 10-20 μm with semi-continuous reticular eutectic θ (Al₂Cu) phases at the grain boundaries. T_B (Al₇Cu₄Li) and T₁ (Al₂CuLi) phases can be observed near the grain boundaries under the influence of thermal cycling. T₁ phases with significant strengthening effects can be observed in the middle and bottom of the sample. The number density of the T₁ phase is higher in the bottom part compared to the middle, but the size of the T₁ phase is relatively larger because the bottom of the sample near the substrate experienced more thermal cycling. The maximum hardness of the as-built Al-Li sample is 126.7 HV_0.1, slightly higher than that of the other wire and arc additive manufactured using 2219 Al-Cu alloys, mainly owing to the fine equiaxed grains and the T₁ phases formed via thermal cycling.