Fig. 1 a Scanning strategy of the SLM process; b SLM printed AlCoCrFeNi2.1 EHEAs bulk morphology; c specimen size for tensile test at room temperature

Fig. 2 Micromorphology a, particle size distribution b, internal defects c, microstructure d of AlCoCrFeNi2.1 raw powder

Fig. 3 a Density as a function of volumetric energy density (VED); b three stages corresponding to the influence of SLM parameters on molding quality

Fig. 4 Micropore aggregation morphology and average volume of different VED samples detected by XCT: a VED 36.6; b VED 68; c VED 95; d VED 109.9; e VED 119; f average defect volume of different VED formed specimens. Red and blue points represent pores with sizes larger and less than 100 μm

Fig. 5 Macromorphologies of a1, b1, c1, d1, e1, X-Y plane, a2, b2, c2, d2, e2 X-Z plane, f roughness statistics of different VED samples

Fig. 6 3D morphological features of the a X-Y plane, b X-Z plane of SLM-printed samples

Fig. 7 a Variation of relative density and porosity at different VED; b fitting functions of X-Y and X-Z plane roughness and porosity

Fig. 8 XRD patterns of SLM-processed AlCoCrFeNi2.1 HEAs samples taken from the plane perpendicular a, a1, parallel b, b1 to the build direction; c the strongest diffraction peak for different surfaces; d phase content statistics of different sections of different VED specimens

Fig. 9 PF corresponding to different plane and phase of SLM samples VED 109.9

Fig. 10 Orientation difference angle distribution map of X-Y plane a, X-Z plane d of VED 109.9 J/mm3 sample; the histogram of grain boundary orientation difference angle distribution in X-Y plane b, X-Z plane e; KAM maps computed from the raw EBSD data of X-Y plane c, X-Z plane f

Fig. 11 a TEM Characterization of X-Z section of VED109.9 specimen; b-d bight-field TEM images of different structures with corresponding SAED patterns; e SEM image of B2 phase particles; f macroscopic morphology of molten pool and element energy spectrum analysis

Fig. 12 a Microhardness values of different surfaces of the tested samples; b the stress-strain curves of tensile tests and tensile strengths and elongation c; d porosity as a function of tensile strength and elongation; nano-indentation morphology of molten pool e and nano-hardness distribution cloud map f

Fig. 13 a-c Macroscopic fracture morphologies corresponding to three stages of AM printed alloys. d-f Fracture micromorphology and local magnification of VED109.9 sample

Fig. 14 Interaction of laser and powder, and two cases of spheroidization: a large size spheroidization; b flat spread micro-bumps