In this paper, the corresponding densification, microstructure, precipitate phase and mechanical properties of Al-14.1Mg-0.47Si-0.31Sc-0.17Zr fabricated by selective laser melting were detailly investigated. The experimental result shows that the densification of SLM specimens increased first and then decreased with energy density. Even at the same energy density, the relative densities of the samples are also different, and the printed sample has a high densification under the condition of low laser power and scanning speed. Two typical microstructures (fine grain zone and coarse grain zone) were formed inside the printed samples due to the formation of Al₃(Sc, Zr) particles (coherent with the Al matrix) during the solidification process of SLM. As fabricated at 200 W and 500 mm/s, the average grain size of the SLM sample is 2.07 (Y-Z plane) and 1.72 μm (X–Y plane), and the maximum values of nano-hardness and tensile strength were 2.19 GPa and 510 MPa, respectively. The mechanical properties increased due to the combined effect of fine grain strengthening and dispersed distribution of precipitates in Al matrix. With a low density (2.537 g/cm³) and high tensile strength, the components fabricated by this alloy have more extensive spreading values and prospects for applying due to the excellent mechanical performance.

本文详细研究了通过选择性激光熔化制备的Al-14.1Mg-0.47Si-0.31Sc-0.17Zr的致密化，组织，析出相和力学性能。实验结果表明，随着能量密度的增加，SLM试样的致密化先增加后减小。即使在相同的能量密度下，样品的相对密度也不同，并且在低激光功率和扫描速度的条件下，打印的样品具有较高的致密性。由于Al ₃的形成，在印刷样品内部形成了两种典型的微观结构（细晶粒区和粗晶粒区）。SLM凝固过程中的（Sc，Zr）颗粒（与Al基体相干）。以200 W和500 mm / s的速度制造时，SLM样品的平均晶粒尺寸为2.07（YZ平面）和1.72μm（X–Y平面），纳米硬度和拉伸强度的最大值为2.19 GPa和分别为510 MPa。机械性能的提高归功于细晶粒强化和析出物在Al基体中分散分布的综合作用。低密度（2.537 g / cm ³）和高拉伸强度，由这种合金制成的部件具有出色的机械性能，因此具有更广泛的铺展值和应用前景。