Multi-Objective Optimization of SLM Process Parameters for AlSi10Mg Alloy to Enhance Mechanical and Microstructural Performance

This study focuses on multi-objective optimization of selective laser melting (SLM) process parameters for AlSi10Mg, targeting mechanical properties, dimensional accuracy, and microstructure before and after annealing. The primary aim of this research is to identify the optimal combination of SLM parameters that simultaneously maximizes the mechanical strength, ductility, and dimensional precision of AlSi10Mg components before and after heat treatment. Optimization was performed using the Taguchi method, principal component analysis (PCA), and a composite desirability function (CDF) optimization, considering the factors of laser power, scan speed, hatch spacing, and scan pattern. Tensile testing, 3D scanning, and scanning electron microscopy (SEM) were used for evaluation. Results show improved performance with the optimized parameters. Elongation increased from 20 % to 21 % (5 %), Young’s modulus from 20 GPa to 57 GPa (2.85 times), tensile strength from 144 MPa to 217 MPa (51 %), and yield strength from 87 MPa to 145 MPa (1.67 times). Post-annealing, strength decreased slightly, but ductility improved significantly. Microstructural analysis revealed a shift from brittle, void-rich fractures to ductile, dimple-rich surfaces. Elemental mapping revealed a more uniform distribution of Si and Mg, accompanied by grain growth and pore spheroidization. Dimensional accuracy was also improved, particularly in critical regions. The integrated optimization approach successfully enhanced both mechanical and microstructural performance, underscoring the importance of controlling both processing and post-processing to produce high-quality AlSi10Mg components.