About this Abstract |
Meeting |
2025 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2025)
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Symposium
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2025 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2025)
|
Presentation Title |
Porosity Reduction in Large-Format Additive Manufacturing of Fiber-Reinforced Composites via Elongational Screw Design |
Author(s) |
Aywan Das, Chad Duty |
On-Site Speaker (Planned) |
Aywan Das |
Abstract Scope |
As Large-Format Additive Manufacturing (LFAM) advances toward structurally demanding applications, internal porosity in extruded fiber-reinforced beads (typically 4–10% by volume) remains a limiting factor for mechanical performance. This study investigates porosity reduction using a single-screw lab-scale extrusion system (Randcastle Microtruder Model RCP-1000) to evaluate the effects of nozzle diameter (3.18 mm and 6.35 mm), temperature (205–250 °C), and screw speed (15–105 rpm) on flow rate, shear rate, viscosity, and porosity in 40 wt% glass fiber-filled ABS. Consistent bead collection was ensured using a conveyor belt, and Archimedes' density analysis was applied to quantify internal voids. Ongoing work compares a conventional screw and a patented Spiral Fluted Elongational Mixer (SFEM) screw from Randcastle Systems to assess the impact of elongational mixing on porosity and melt homogeneity. This study aims to establish extrusion parameter–porosity relationships and inform design decisions for next-generation LFAM systems using highly filled reinforced polymer composites. |
Proceedings Inclusion? |
Planned: Post-meeting proceedings |