Thin-walled structures are increasingly used in advanced engineering, yet their precise fabrication via metal Additive Manufacturing remains challenging. Pulsed Wave Laser Powder Bed Fusion (PBF-LB/M) offers strong potential for producing micro-scale features, but the combined effects of pulse enthalpy (which is related to energy) and spatial pulse overlap strategies on thin-wall quality remain underexplored. This study investigates how variations in pulse enthalpy and spacing between discrete laser points—controlling pulse overlap—influence the geometry and mechanical performance of thin walls fabricated along a single contour. Five point-spacing values yielding different overlap percentages were tested for three enthalpy levels. Resulting walls (130 to 320 μm thick) were evaluated for geometry (thickness, waviness), mechanical properties (tensile strength, toughness), failure modes, and microstructure. Results showed that low-enthalpy inputs supported minimal overlap (down to 10%) without compromising mechanical integrity, increasing build efficiency. In contrast, high enthalpy induced keyhole formation, requiring greater overlap to maintain structural integrity. Three empirical models were developed to relate: (i) enthalpy to melt-pool diameter (R 2 = 0.98), (ii) enthalpy and overlap to wall thickness (R 2 = 0.98), and (iii) enthalpy and overlap to ultimate tensile strength (R 2 = 0.89). These models were integrated into a parameter optimization tool within the investigated process window , that enabled the fabrication of geometrically accurate thin walls (<1% deviation) and over 20% reduction in build time versus standard parameters. This work introduces a systematic workflow for parameter optimization in pulsed-wave PBF-LB/M, based on enthalpy-driven process descriptors.
Giannetto et al. (2026) studied this question.