Fig. 1. Morphology of Al-Mg-Sc-Zr alloy powders

Fig. 2. Schematic diagram of SLM scanning strategy (z-direction is the deposition direction)

Fig. 3. Tensile test. (a) Schematic diagram of tensile specimen size; (b) photo of SLM forming specimen

Fig. 4. X-CT test results. (a) 3D reconstructed image of defects; (b) frequency distribution of pore defect size; (c) frequency distribution of pore defect sphericity

Fig. 5. OM images of Al-Mg-Sc-Zr alloy formed by SLM. (a) Vertical plane; (b) horizontal plane

Fig. 6. SEM images of Al-Mg-Sc-Zr alloy formed by SLM. (a) Entire melt pool; (b) melt pool boundary

Fig. 7. EBSD results of Al-Mg-Sc-Zr alloy formed by SLM. (a) EBSD IPF of melt pool; (b) EBSD IPF of fine grain region at melt pool boundary; (c) grain size distribution throughout the melt pool; (d) grain size distribution of fine grain region at melt pool boundary

Fig. 8. SEM morphology of tensile fracture of Al-Mg-Sc-Zr alloy formed by SLM