Computational analysis of the extrusion process of fused deposition modeling of acrylonitrile-butadiene-styrene

Shadvar, Nafiseh; Foroozmehr, Ehsan; Badrossamay, Mohsen; Amouhadi, Iman; Dindarloo, Alireza Shojaei

doi:10.1007/s12289-019-01523-1

Cited by 25 publications

(12 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In terms of the print temperature, die swell decreases as the temperature increases since the polymer chains have enhanced molecular mobility that aid stress–relaxation due to higher free volume around the chains. A recent study on FEM simulations of the die-swell characteristics of ABS during FFF reported that increased nozzle temperature and lower material flow rates (lower print speeds) resulted in reduced die-swell of the extrudate due to the reasons discussed above . The theoretical analysis underpredicted the extent of die swell by approximately 20%.…”

Section: Importance Of Polymer Rheology In Materials Extrusion Based Ammentioning

confidence: 97%

Importance of Polymer Rheology on Material Extrusion Additive Manufacturing: Correlating Process Physics to Print Properties

Das

Gilmer

Biria

et al. 2021

ACS Appl. Polym. Mater.

147

View full text Add to dashboard Cite

Recent advances in the field of additive manufacturing (AM) or 3D printing, have garnered serious interest for its potential to substitute time-consuming and costly subtractive and formative manufacturing techniques. Material extrusion (MatEx), employing filament and pelletbased feedstocks, is an AM technique for fabricating three-dimensional objects dictated by a computer-aided design (CAD) file in a layer-by-layer manner. Being inherently a "melt-and-form" technique, the physics of MatEx is strongly dependent on the melt flow behavior of the polymers and hence on their rheology. The focus of this review article is to analyze the current progress in rheological characterizations of filament and pellet-based polymeric feedstocks for application in MatEx. The importance of shear and temperature-dependent viscosities in relation to consistent extrusion through the print nozzle and in the standoff region between nozzle and bed will be highlighted. The importance of shear and/or extensional viscosities and extent of die swell (upon exit from the nozzle) experienced by the polymers under processing parameters relevant to MatEx will be investigated. Postextrusion from the nozzle, the rheological characteristics of the viscous polymer melt as it cools once deposited on the print bed governs the degree of interlayer welding, that impacts the mechanical performance of the printed parts. Controlling and monitoring rheological properties such as zero-shear viscosities and shear moduli of the melt is of significant importance in this region in order to ensure proper mechanical robustness and shape integrity of the deposited layers. Both experimental and theoretical approaches based on polymer chain reptation mechanisms will be reviewed in detail and suggestions to address the existing limitations associated with the process will be provided. Fundamental understanding of the correlation between the classical theories and current understanding based on recent experimentation and analysis is expected to assist the design and development of the next generation of polymer feedstocks and machine designs for MatEx-based AM.

show abstract

Section: Importance Of Polymer Rheology In Materials Extrusion Based Ammentioning

confidence: 97%

Importance of Polymer Rheology on Material Extrusion Additive Manufacturing: Correlating Process Physics to Print Properties

Das

Gilmer

Biria

et al. 2021

ACS Appl. Polym. Mater.

147

View full text Add to dashboard Cite

show abstract

“…Yang and Zhang [ 23 ] also investigated the thermal history an FFF printed part with different infill patterns through the finite element approach, where the honeycomb infill was shown to result a minimum temperature gradient. Shadvar et al [ 24 ] studied the die swell of ABS polymer during the FFF extrusion process through the finite element suite ANSYS-Polyflow and showed that die swell played a key role in improving the dimensional accuracy of FFF parts. Additional earlier efforts beyond the recent three years for the modelling of polymer deposition processes can be found in related review articles such as [ 25 , 26 ].…”

Section: Introductionmentioning

confidence: 99%

A Fully Coupled Simulation of Planar Deposition Flow and Fiber Orientation in Polymer Composites Additive Manufacturing

Wang

Smith

2021

Materials

View full text Add to dashboard Cite

Numerical studies for polymer composites deposition additive manufacturing have provided significant insight promoting the rapid development of the technology. However, little of existing literature addresses the complex yet important polymer composite melt flow–fiber orientation coupling during deposition. This paper explores the effect of flow–fiber interaction for polymer deposition of 13 wt.% Carbon Fiber filled Acrylonitrile Butadiene Styrene (CF/ABS) composites through a finite-element-based numerical approach. The molten composite flow in the extrusion die plus a strand of the deposited bead contacting the deposition substrate is modelled using a 2D isothermal and incompressible Newtonian planar flow model, where the material deposition rate is ~110 mm/s simulating a large scale additive manufacturing process. The Folgar–Tucker model associated with the Advani–Tucker orientation tensor approach is adopted for the evaluation of the fiber orientation state, where the orthotropic fitted closure is applied. By comparing the computed results between the uncoupled and fully coupled solutions, it is found that the flow-orientation effects are mostly seen in the nozzle convergence zone and the extrusion-deposition transition zone of the flow domain. Further, the fully coupled fiber orientation solution is highly sensitive to the choice of the fiber–fiber interaction coefficient , e.g., assigning as 0.01 and 0.001 results in a 23% partial relative difference in the predicted elastic modulus along deposition direction. In addition, Structural properties of deposited CF/ABS beads based on our predicted fiber orientation results show favorable agreements with related experimental studies.

show abstract

“…For the FiberFlex 40D, the value increased slightly to 0.38 mm, whereas for the FilaFlex 95A and Yousu 98A, even a thickness of 0.47 and 0.535 mm could be measured, respectively. Due to the reason that all substrates were printed with the same parameters, it can be assumed that the different die swelling of the different TPUs will cause different dimensions in thickness and width ( Nikzad et al, 2011 ; Shadvar et al, 2021 ). It is obvious that those strips that show higher width also result in higher thickness because of the die swell effect.…”

Section: Resultsmentioning

confidence: 99%

Fabrication of a Soft Robotic Gripper With Integrated Strain Sensing Elements Using Multi-Material Additive Manufacturing

2021

View full text Add to dashboard Cite

With the purpose of making soft robotic structures with embedded sensors, additive manufacturing techniques like fused deposition modeling (FDM) are popular. Thermoplastic polyurethane (TPU) filaments, with and without conductive fillers, are now commercially available. However, conventional FDM still has some limitations because of the marginal compatibility with soft materials. Material selection criteria for the available material options for FDM have not been established. In this study, an open-source soft robotic gripper design has been used to evaluate the FDM printing of TPU structures with integrated strain sensing elements in order to provide some guidelines for the material selection when an elastomer and a soft piezoresistive sensor are combined. Such soft grippers, with integrated strain sensing elements, were successfully printed using a multi-material FDM 3D printer. Characterization of the integrated piezoresistive sensor function, using dynamic tensile testing, revealed that the sensors exhibited good linearity up to 30% strain, which was sufficient for the deformation range of the selected gripper structure. Grippers produced using four different TPU materials were used to investigate the effect of the Shore hardness of the TPU on the piezoresistive sensor properties. The results indicated that the in situ printed strain sensing elements on the soft gripper were able to detect the deformation of the structure when the tentacles of the gripper were open or closed. The sensor signal could differentiate between the picking of small or big objects and when an obstacle prevented the tentacles from opening. Interestingly, the sensors embedded in the tentacles exhibited good reproducibility and linearity, and the sensitivity of the sensor response changed with the Shore hardness of the gripper. Correlation between TPU Shore hardness, used for the gripper body and sensitivity of the integrated in situ strain sensing elements, showed that material selection affects the sensor signal significantly.

show abstract

Computational analysis of the extrusion process of fused deposition modeling of acrylonitrile-butadiene-styrene

Cited by 25 publications

References 18 publications

Importance of Polymer Rheology on Material Extrusion Additive Manufacturing: Correlating Process Physics to Print Properties

Importance of Polymer Rheology on Material Extrusion Additive Manufacturing: Correlating Process Physics to Print Properties

A Fully Coupled Simulation of Planar Deposition Flow and Fiber Orientation in Polymer Composites Additive Manufacturing

Fabrication of a Soft Robotic Gripper With Integrated Strain Sensing Elements Using Multi-Material Additive Manufacturing

Contact Info

Product

Resources

About