In this work, the selective laser melting (SLM) of Sc and Zr modified Al-Mn alloy was systematically investigated, with a particular emphasis on the density behavior, microstructure and mechanical properties. The process parameters were significantly impact on the relative density and the maximum relative density of SLM-processed Al-Mn-Sc-Zr specimens reached 99.8% at the optimized process parameters. With the reduction of energy density, the melting mode of melting pool changed from keyhole mode to conduction mode. At the high energy density, near-spherical pores were generated because of the evaporation of low melting alloy constituents. With the decreasing of energy density, irregular pores were generated, which was mainly caused by the insufficient energy input. The SLM processed Al--Mn-Sc-Zr showed a duplex grain microstructure consisting of regions of columnar grains and equiaxed grains. Good mechanical properties were reached in as-fabricated condition: tensile strength ≥ 426 MPa and elongation to fracture ≥ 18%. Besides, no significant anisotropy was found in the stress–strain behavior between horizontal and vertical building direction.

在这项工作中，系统地研究了 Sc 和 Zr 改性 Al-Mn 合金的选择性激光熔化 (SLM)，特别强调了密度行为、微观结构和机械性能。工艺参数对相对密度有显着影响，在优化的工艺参数下，SLM处理的Al-Mn-Sc-Zr试样的最大相对密度达到99.8%。随着能量密度的降低，熔池的熔化模式由锁孔模式转变为传导模式。在高能量密度下，由于低熔点合金成分的蒸发，产生了接近球形的孔隙。随着能量密度的降低，会产生不规则的孔隙，这主要是由于能量输入不足造成的。SLM 加工的 Al--Mn-Sc-Zr 显示出由柱状晶粒和等轴晶粒区域组成的双相晶粒显微组织。在制造条件下达到了良好的机械性能：拉伸强度 ≥ 426 MPa 和断裂伸长率 ≥ 18%。此外，在水平和垂直建筑方向之间的应力应变行为中没有发现显着的各向异性。