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Fused filament fabrication (FFF) is one of the most accessible and flexible additive manufacturing processes. However, it is plagued by consistency issues related to material deposition. The role of compressibility is explored with an instrumented nozzle to relate the observed printing pressure to variations in deposited road widths. Variations in road width are analyzed relative to those predicted using a double domain Tait equation (PVT model) for high impact polystyrene (HIPS). Compressibility was found a critical effect, varying the road widths by up to 50% when accelerating and decelerating. The effect of the speed of transient stress propagation was also investigated but found insignificant.
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Compressibility in Fused Deposition Modeling
Fused deposition modeling (FDMTM), also referred to as fused filament fabrication (FFF) is an additive manufacturing technique in which extruded material is deposited into roads and layers to form complex products. This paper provides a physics-based model for predicting and controlling the effect of compressibility in material extrusion including elasticity in the driven filament and compression of the melt in the hot end. The model is validated with a test part embodying a full factorial design of experiments with three print speeds. The model is used for control and shows elimination of 50% of the associated road width variance due to compressibility, thereby enabling higher quality levels even at higher print speeds.
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- Award ID(s):
- 1914651
- PAR ID:
- 10341316
- Date Published:
- Journal Name:
- Society of Plastics Engineering Annual Technical Conference, Additive Manufacturing Division
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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