Abstract
The mechanical properties of Fused Filament Fabrication (FFF) parts are limited in the build direction, albeit advantages such as design flexibility and in-house customization. In this paper, a novel z-pinning approach that enhances mechanical properties in the build direction by depositing material across multiple layers within the part was investigated through numerical simulations and validated experimentally. A finite element model for z-pinned composite structures was developed by assigning fiber-orientation dependent material properties obtained using a micromechanics approach to beads and pins. The bead-to-bead and pin-to-pin adhesions within the z-pinned structures were modeled using a cohesive traction separation law. The properties of cohesive elements for carbon fiber-reinforced polylactic acid (CF-PLA) z-pinned composites were calibrated using tensile experiments. The elastic modulus and tensile strength of CF-PLA z-pinned composites in the build direction were predicted with the developed numerical model. The numerical investigation on various geometrical parameters revealed that the largest pin volume increases the stiffness and tensile strength by 40% and thus, has the greatest influence on the mechanical properties of the z-pinned composites. The effect of z-pin geometrical parameters on the mechanical properties was summarized to aid in the design of z-pinned additively manufactured composite structures.
| Original language | English |
|---|---|
| Article number | 105735 |
| Journal | Materials Today Communications |
| Volume | 35 |
| DOIs | |
| State | Published - Jun 2023 |
Funding
Notice: This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05–00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the work for publication, acknowledges that the US government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the submitted manuscript version of this work, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). Portions of the research were supported by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Industrial Technologies Program , under contract DE-AC05–00OR22725 with UT-Battelle, LLC. The authors gratefully acknowledge support from U.S. Army Combat Capabilities Development Command Aviation & Missile Center (DEVCOM AvMC) (DISTRIBUTION A, approved for public release, distribution is unlimited, PR20221280 ). The authors express gratitude to Amiee Jackson for developing some of the SolidWorks models. The material modeling results reported were obtained using AlphaSTAR Technology Solution’s commercially available material characterization and qualification platform, MCQ software. Portions of the research were supported by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Industrial Technologies Program, under contract DE-AC05–00OR22725 with UT-Battelle, LLC. The authors gratefully acknowledge support from U.S. Army Combat Capabilities Development Command Aviation & Missile Center (DEVCOM AvMC) (DISTRIBUTION A, approved for public release, distribution is unlimited, PR20221280). The authors express gratitude to Amiee Jackson for developing some of the SolidWorks models. The material modeling results reported were obtained using AlphaSTAR Technology Solution's commercially available material characterization and qualification platform, MCQ software.
| Funders | Funder number |
|---|---|
| Office of Energy Efficiency and Renewable Energy, Industrial Technologies Program | DE-AC05–00OR22725 |
| U.S. Department of Energy | |
| U.S. Army Combat Capabilities Development Command Aviation and Missile Center | PR20221280 |
Keywords
- 3D Printing
- Anisotropy
- Fused filament fabrication
- Interlayer strength
- Polymer composites
