Journal article
A shape-predictive model for the spreading of photo-curable polymers in material extrusion additive manufacturing
Additive manufacturing, v 85, 104163
05 Apr 2024
Abstract
Recently, there is a growing interest in material extrusion to print thermoset resins to manufacture large format and high-performance parts. However, the fidelity and mechanical integrity of the printed parts are limited by challenges such as uncontrolled spreading of individual beads (filament/droplet) after deposition and during cure. There is a considerable lack of experimental and theoretical studies on the spreading of reactive beads on solid substrates. In this work, we studied the simultaneous spreading and photo-curing of the photopolymerizable thermoset beads via experiment and numerical simulations. We used a novel experimental setup to track the spreading of droplets and filaments during photopolymerization and validate a moving mesh computational fluid dynamics (CFD) model. The CFD model was used to develop an approach (predictive model) to accurately predict the final spreading coefficient of cured resin beads without the need for full numerical simulations. The predictive model combines the generalized theory of a Newtonian spreading filament with a characteristic viscosity μave and time to gelation, τgel. Interestingly, μave is shown to be a material parameter that does not depend on processing conditions, but only on the material’s chemorheology. The predictive model is tested against a wide range of chemorheology and cure kinetic parameters and found to be in excellent agreement with the full numerical CFD simulations. This work will be very useful in estimating the final shape of beads during the material extrusion printing process, as well as a model to successfully parameterize extrusion-based 3D printers to control the shape of printed beads a-priori.
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• Spreading of curing droplets/filaments on solid substrate is studied.
• A predictive model to estimate the final shape of curing beads is developed.
• Spreading of curing resins is characterized by average viscosity and gelation time.
• Predictive-model is used in extrusion-based printer to control bead shape a-priori.
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Details
- Title
- A shape-predictive model for the spreading of photo-curable polymers in material extrusion additive manufacturing
- Creators
- Amir Azimi YancheshmeHeedong YoonGiuseppe R. PalmeseNicolas J. Alvarez (Corresponding Author)
- Publication Details
- Additive manufacturing, v 85, 104163
- Publisher
- Elsevier
- Number of pages
- 9
- Grant note
- Army Research Laboratory, USA: W911NF-17-2-0227 National Science Foundation, USA: CBET-1847140
Research was sponsored by the Army Research Laboratory, USA and was accomplished under Cooperative Agreement Number W911NF-17-2-0227. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Army Research Laboratory or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes not withstanding any copyright notation herein. NJA was also supported by the National Science Foundation, USA under grant no. CBET-1847140.
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- Chemical and Biological Engineering
- Web of Science ID
- WOS:001299296600001
- Scopus ID
- 2-s2.0-85192008450
- Other Identifier
- 991021876015204721
InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool:
- Web of Science research areas
- Engineering, Manufacturing
- Materials Science, Multidisciplinary