Al-6.0Mg-0.3Sc alloy deposits are prepared by means of a double-wire arc additive manufacturing process. The formation, porosity, metallographic structure, type of precipitated phase, and mechanical properties of the deposit are studied. Double-wire arc forming affords precision advantages over single-wire-arc forming, which is evidenced by the increased surface uniformity of the deposit. Compared with the deposit of single-wire-arc formed, the deposit of double-wire arc formed exhibits only fewer and smaller pores, and the lower process heat yields rapid solidification and tiny precipitate sizes. A larger amount of Mg and Mn is observed to be dissolved in the Al matrix of double-wire arc-formed deposit, which increases the alloy strength, and smaller primary Al₃Sc phase, which exhibits excellent grain refinement. Furthermore, the presence of a high amount of Sc solid solution in the matrix of double-wire arc-formed deposit strengthens the alloy, and the melting of the rear wire “heat-treats” the substrate formed by the front wire, promotes secondary Al₃Sc phase precipitation, and further strengthens the alloy. Compared with the deposit of single-wire-arc formed, the mechanical properties of double-wire arc-formed deposit show an improvement: the tensile strength, yield strength, and elongation of the horizontally oriented specimens are estimated as 363 MPa, 258 MPa, and 26%, respectively. This successful implementation of the cold metal transfer + pulse process to prepare Al-Mg alloy parts can pave the way to their industrial production. The proposed method can find wide utility in the fields of aviation, aerospace, military, and shipbuilding.

中文翻译：

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双丝电弧增材制造沉积Al-6.0Mg-0.3Sc合金的组织与性能

Al-6.0Mg-0.3Sc合金镀层采用双丝电弧增材制造工艺制备。研究了沉积物的形成、孔隙率、金相结构、析出相类型和力学性能。与单线电弧成形相比，双线电弧成形具有精度优势，沉积物表面均匀性的提高就证明了这一点。与单丝电弧成形的沉积物相比，双丝电弧成形的沉积物仅表现出较少且较小的孔隙，并且较低的工艺热量导致快速凝固和微小的析出物尺寸。双丝电弧成形沉积物的Al基体中固溶了较多的Mg和Mn，提高了合金的强度，并且初生Al 3 Sc相较小，具有良好的晶粒细化_作用。此外，双丝电弧沉积基体中存在大量Sc固溶体，强化了合金，后丝的熔化对前丝形成的基体进行了“热处理”，促进了二次Al的形成。₃ Sc相析出，进一步强化了合金。与单丝电弧成型熔敷相比，双丝电弧成型熔敷的力学性能有所改善：水平取向试样的抗拉强度、屈服强度和伸长率估计分别为363 MPa、258 MPa、和 26% 分别。此次成功实施冷金属转移+脉冲​​工艺制备铝镁合金零件，为其工业化生产铺平了道路。所提出的方法可以在航空、航天、军事和造船领域得到广泛的应用。