Thermal Process Modeling and Powder-Bed Packing Simulation for Laser Powder Bed Fusion of AA6061 Alloy

Additive manufacturing via laser powder bed fusion (LPBF) enables rapid fabrication of complex structures; however, AA6061 remains less explored than alloys such as AlSi10Mg. This study employs complementary numerical approaches to analyze two critical aspects of LPBF processing for thin AA6061 aerospace structures. First, we integrated temperature-dependent thermophysical properties into a transient finite-element model in ANSYS Mechanical APDL Release 15.0.7 (R15.0) to assess thermal responses across varying laser powers, scanning speeds, and hatch spacings. A comparison with a previous experimental study revealed discrepancies of approximately 6–16% between predicted and measured melt-pool dimensions under the investigated processing conditions. Second, a MATLAB R2018a-based particle-generation routine simulated 3D spherical powder beds. Among the investigated conditions, 75,000 to 100,000 particle-placement attempts yielded the highest powder-bed packing fractions. The coordinates and radii were successfully transferred to COMSOL Multiphysics 5.3 for 3D geometric reconstruction, demonstrating cross-platform compatibility. The results demonstrate that thermal and powder-bed modeling provide complementary insights into processing conditions, distinct from final-part densification. These computational approaches lay the foundation for minimizing experimental trials and developing future coupled models of particle-scale behavior, melt-pool evolution, porosity, and part densification.