Laser powder bed fusion of AlSi10Mg alloy; productivity and cost analysis

The growing application of additive manufacturing (AM) has revolutionized modern production, offering design freedom, material reduction, and rapid production. Of the various AM processes, Laser Powder Bed Fusion (L-PBF) is a leading process for manufacturing metal components with complex geometries and high mechanical properties. Its capability to utilize advanced materials like AlSi10Mg makes it attractive for aerospace, automotive, and biomedical applications. However, L-PBF is challenged with maximizing productivity, quality of parts, and reducing costs. In this study, the influence of major process parameters on AlSi10Mg manufacturing is investigated to enhance productivity while ensuring high-quality, low-cost production. The present study targets four key L-PBF parameters—layer thickness, laser power, scan speed, and hatch distance—and their influence on critical quality factors like density, porosity, surface roughness, and mechanical properties. In addition, a cost analysis examines the economic feasibility of the different processing conditions. With a systematic experimental approach, 54 cube samples were produced utilizing a Prima Additive PrintSharp 250 L-PBF apparatus. Two experiments were conducted utilizing 40 µm and 60 µm layer thicknesses and varying laser power (310–390 W), scan speed (1200–1600 mm/s), and hatch distance (0.11–0.13 mm). These parameters were assessed based on their impact on volumetric energy density (VED), an important measure that affects part densification. Density and porosity were quantified using Archimedes density measurement, X-ray computed tomography (XCT), and metallography with image analysis. Results showed that higher VED values optimized relative density, which reached 99.3% in an optimal range of 30–40 J/mm³. High VED (>50 J/mm³), on the other hand, resulted in keyhole-induced porosity due to excessive vaporization, while low VED resulted in lack-of-fusion defects. ANOVA analysis revealed that scan speed and layer thickness significantly influenced density, whereas laser power and hatch distance had a minimal effect. Samples with 60-µm layer thickness exhibited marginally higher densities than 40-µm samples, which indicates improved densification under optimal conditions. Surface roughness (Ra) was measured using profilometry, ranging from 3.04 µm to 17.65 µm. Thicker layers, higher scan speeds, and larger hatch distances increased surface roughness, while greater laser power and middle scan speeds improved surface quality. A high negative correlation between VED and roughness was found, where higher VED stabilized the melt pool and resulted in a smoother surface. Higher VED, however, created rougher surfaces due to overheating. Mechanical properties were evaluated by compression testing, noting yield strength, ultimate compressive strength (UCS), and failure strain. Density showed a close correlation with mechanical performance, with dense samples having increased strength. Less porous samples were found to possess lower mechanical properties, emphasizing the need for optimal process parameters to ensure structural integrity. Results validated that layer thickness, scan speed, and hatch distance had a significant effect on mechanical performance, which emphasizes the need for accurate L-PBF parameter tuning for industrial purposes.