A Review on Emerging Granule-Based 3D Printing Technology
Subject Areas :Atefeh Nejadebrahim 1 * , Zeinab Akbarian 2
1 -
2 - Polymer Engineering Department, Qom University of Technology, P.O. Box: 1519-37195, Qom, Iran
Keywords: 3D Printing, Material Extrusion Printing, Fused Granular Fabrication, Biocompatible Polymers,
Abstract :
Fused granular fabrication, as an emerging extrusion-based additive manufacturing technology, has gained increasing attention as a promising alternative to conventional filament-based systems due to its direct utilization of polymer pellets as feedstock. Eliminating the intermediate filament production step not only reduces material and processing costs but also enhances flexibility in material selection and enables the development of diverse polymeric and composite formulations. These advantages position pellet-based printing as a suitable approach for manufacturing engineering components, biocompatible structures, and large-scale applications.
The performance of pellet-fed systems is strongly influenced by the intrinsic properties of the feedstock and the processing parameters. In polymer composites, filler characteristics—including type, particle size, morphology, aspect ratio, and dispersion quality within the polymer matrix—play a critical role in determining melt rheological behavior, extrusion stability, interlayer adhesion, dimensional accuracy, and the final mechanical and functional properties of printed parts. Therefore, successful design of printable formulations requires a comprehensive understanding of the interactions among material structure, filler characteristics, and processing conditions.
This review article discusses the fundamentals, advantages, challenges, and applications of granule-based 3D printing and provides a technical and economic comparison with filament-based additive manufacturing. Furthermore, the role of biocompatible polymers and composite systems, the influence of filler characteristics on printability and part performance, and the major challenges in advancing this technology are examined. Finally, future research directions aimed at improving print quality, developing advanced materials, and expanding industrial and biomedical applications are outlined.
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