PurposeMaterial extrusion additive manufacturing of feedstocks highly loaded with metal powders (MEX-M) is an emerging method for producing fully metallic components. This study aims to investigate the feasibility of using filament-based MEX-M to fabricate soft ferromagnetic parts and characterizes their magnetic properties.Design/methodology/approachToroidal specimens were produced by MEX-M using a commercial PLA-based 81 Wt.% Fe filament and a desktop printer. Air thermal debinding was screened by varying heating rate and crucible configuration, and assessed by mass loss and cross-sectional analysis. Using the best cycle, parts were sintered at three temperatures under low vacuum; additional specimens underwent continuous debinding and sintering at the intermediate condition in vacuum or Ar. Density, shrinkage and B-H loops were measured before and after post-sinter vacuum annealing.FindingsLow-vacuum sintering at 1,350 degrees C yielded the best results: 92% relative density and saturation magnetization BS = 1.15 T, 65% of commercial pure iron. Vacuum annealing increased BS by up to 10% and reduced coercivity by up to 60%. Oxygen shielding, debinding ramps below 40 K/h and sintering at = 1,350 degrees C limited void formation and deformation, yet residual internal voids persisted across all conditions.Originality/valueTo the best of the authors' knowledge, this is the first demonstration of fabricating high-density unalloyed magnetic steel components via filament-based MEX-M. The analysis of debinding and sintering parameters contributes to future filament formulation and process optimization to advance the state of the art.
Investigation on the material extrusion additive manufacturing of unalloyed magnetic steel
Marconcini, Francesco;Giammarinaro, Guido;Tamburrino, Francesco;Caposciutti, Gianluca;Neri, Paolo;Paganucci, Fabrizio;Razionale, Armando Viviano
2026-01-01
Abstract
PurposeMaterial extrusion additive manufacturing of feedstocks highly loaded with metal powders (MEX-M) is an emerging method for producing fully metallic components. This study aims to investigate the feasibility of using filament-based MEX-M to fabricate soft ferromagnetic parts and characterizes their magnetic properties.Design/methodology/approachToroidal specimens were produced by MEX-M using a commercial PLA-based 81 Wt.% Fe filament and a desktop printer. Air thermal debinding was screened by varying heating rate and crucible configuration, and assessed by mass loss and cross-sectional analysis. Using the best cycle, parts were sintered at three temperatures under low vacuum; additional specimens underwent continuous debinding and sintering at the intermediate condition in vacuum or Ar. Density, shrinkage and B-H loops were measured before and after post-sinter vacuum annealing.FindingsLow-vacuum sintering at 1,350 degrees C yielded the best results: 92% relative density and saturation magnetization BS = 1.15 T, 65% of commercial pure iron. Vacuum annealing increased BS by up to 10% and reduced coercivity by up to 60%. Oxygen shielding, debinding ramps below 40 K/h and sintering at = 1,350 degrees C limited void formation and deformation, yet residual internal voids persisted across all conditions.Originality/valueTo the best of the authors' knowledge, this is the first demonstration of fabricating high-density unalloyed magnetic steel components via filament-based MEX-M. The analysis of debinding and sintering parameters contributes to future filament formulation and process optimization to advance the state of the art.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
