A Comprehensive Bulk Parametric Study for Additive Manufacturing of Pure Iron via Laser Powder Bed Fusion

Additive manufacturing of pure iron by Laser Powder Bed Fusion (L-PBF) offers 6 a route to a new generation of patient-specific, biodegradable orthopedic implants 7 with engineered mechanical and corrosion behavior. This work systematically invest- 8 igated bulk L-PBF processing parameters through four sequential build jobs. First, 9 single-track and single-layer scans were performed for 140 parameter combinations 10 by varying laser power (100W to 400W), scan speed (200mms−1 to 1400mms−1), 11 and spot diameter (70 μm to 200 μm). Second, 5 × 5 × 5mm3 cubes were printed 12 and visually inspected to identify stable melting regimes. Third, 5×5×7mm3 par- 13 allelepipeds were produced and evaluated for porosity determination via Image J. 14 Fourth, specimens with unsupported 45° overhangs and horizontal supportless holes 15 were fabricated to assess geometric fidelity and powder entrapment, porosity, and 16 hardness. The data was analysed using analysis of variance (ANOVA), Scott–Knott 17 post-hoc test, and contour plotting of volumetric energy density and energy intens- 18 ity. Results reveal a primary robust processing window at Ev ≈ 47–55 Jmm−3 and 19 Ei ≈ 1.6 × 104–2.6 × 104 Jmm−2, characterized by parts with consistent porosity 20 values below 1%, and hardness exceeding 140 HV; smaller processing windows up 21 to Ev ≈ 75 Jmm−3 yield similar density and mechanical integrity. These bulk- 22 parameter developments lay the groundwork for subsequent mechanical and micro- 23 structural characterization, contour-, skin-, and thin-feature parameter sets, and 24 biocompatibility and biodegradation evaluations of pure iron parts produced by L- 25 PBF.