Wire arc additive manufacturing (WAAM) is a promising approach to producing large-scale metal structures. The investigation on the WAAM of aluminum alloys has lasted for over 17 years and covered multiple alloy systems. However, fundamental research on the WAAM of quaternary Al-Zn-Mg-Cu alloys is still lacking. This study focuses on understanding the microstructural characteristics and mechanical properties of an ultra-high-strength Al-Zn-Mg-Cu alloy fabricated by WAAM. A single-pass multilayer component is successfully fabricated. Results indicate that a single deposition layer consists of two types of columnar grains with different textures and origins. Nanoscale second phases are observed to precipitate during the manufacturing process with location-dependent sizes and volume fractions due to different thermal histories. The microhardness of the cross-section exhibits a special un-uniform distribution between 75–164 HV_0.2 from the substrate to the top of the component. The WAAM deposited component shows higher overall tensile properties than the as-fabricated spray formed counterpart. The average yield strength and ultimate strength are higher in the vertical direction than in the horizontal direction, while the difference in elongation is small.

电弧增材制造（WAAM）是生产大型金属结构的有前途的方法。铝合金WAAM的研究已经进行了17年以上，涉及多种合金体系。但是，仍缺乏对四元Al-Zn-Mg-Cu合金WAAM的基础研究。这项研究的重点是了解WAAM制造的超高强度Al-Zn-Mg-Cu合金的显微组织特征和力学性能。单通道多层组件已成功制造。结果表明，单个沉积层由两种类型的具有不同纹理和起源的柱状晶粒组成。观察到纳米级的第二相在制造过程中由于不同的热历史而以取决于位置的尺寸和体积分数沉淀。从基板到组件顶部的距离为_0.2。WAAM沉积的组件比制成的喷涂成型组件显示出更高的总体拉伸性能。垂直方向的平均屈服强度和极限强度高于水平方向，而伸长率的差异较小。