Compression and Bending Properties of Short Carbon Fiber Reinforced Polymers Sandwich Structures Produced via Fused Filament Fabrication Process
Abstract
:1. Introduction
2. Materials and Methods
2.1. Design of Composite Sandwich Structures
2.2. Design of Wing Sections
2.3. Manufacture of Sandwich Specimens and Wing Sections Using the FFF Process
2.3.1. Materials
2.3.2. Manufacture of Composite Sandwich Specimens
2.4. Testing of Composite Sandwich Specimens
3. Results and Discussion
3.1. Flatwise Compression Performance of Carbon Fiber Sandwich Structures
3.2. Three-Point Bending Behavior of Carbon Fiber Sandwich Structures
- In the first domain, a linear elastic behavior of composite sandwich structures was observed. At the beginning of this domain, for Hat core specimens, the force increases and corresponds to a smaller displacement. This clearly demonstrates that the bending stiffness of this sandwich structure is enhanced by the shear stiffness of the Hat core;
- The second domain comprises the final range of the curve and corresponds to the nonlinear behavior of the material until the sudden rupture of the composite sandwich specimens. The end of this area highlights the failure mode of the composite sandwich structures. The core is shear loaded, and its failure occurs as the critical value (shear strength) of the core material is reached by the maximum shear stress.
3.3. Bending Performance of Wing Sections
3.4. Microscopic Analysis of Composite Sandwich Structures
3.5. Analysis of the Specific Strength-to-Mass Ratio of Composite Specimens
- For compression tests, H core composite sandwich structures have the highest value; it turns out that this structure can be used for aeronautical components whose main requirement is compression. It can also be seen that the specimens with the Z-core sandwich structure have a higher ratio compared to the C-core structures. This is due to the fact that the Z-core, through the flanges positioned to the left and right of the core, absorbs the compression force much better.
- For the three-point bending tests, the sandwich structures showed a very close strength-to-mass ratio. However, C-core sandwich structures showed the highest strength-to-mass ratio, as confirmed by the frequent use of this structure in the wing airframes for small aircraft and unmanned aerial vehicles.
3.6. Bending Finite Element Analysis of Composite Wing Sections
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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FFF Parameters | Value |
---|---|
Infill density [%] | 100 |
Layer height [mm] | 0.2 |
Printing speed [mm/sec] | 50 |
Extrusion temperature [°C] | 260 |
Bed Temperature [°C] | 100 |
Nozzle diameter [mm] | 0.6 |
Composite Sandwich Specimens | Mean (m) | Standard Deviation (s) | Coefficient of Variation (CV)% |
---|---|---|---|
C core—Compressive Strength (MPa) | 5.60 | 0.55 | 9.78 |
Z core—Compressive Strength (MPa) | 6.20 | 0.45 | 7.21 |
Hat core—Compressive Strength (MPa) | 14.00 | 1.22 | 8.75 |
C core—Compressive Modulus (GPa) | 0.25 | 0.02 | 8.99 |
Z core—Compressive Modulus (GPa) | 0.26 | 0.02 | 8.00 |
Hat core—Compressive Modulus (GPa) | 0.44 | 0.03 | 6.81 |
Composite Sandwich Specimens | Mean (m) | Standard Deviation (s) | Coefficient of Variation (CV)% |
---|---|---|---|
C core—Bending Strength (MPa) | 12.40 | 0.55 | 4.43 |
Z core—Bending Strength (MPa) | 12.20 | 1.10 | 9.01 |
Hat core—Bending Strength (MPa) | 17.00 | 0.71 | 4.17 |
C core—Bending Modulus (GPa) | 0.49 | 0.01 | 2.04 |
Z core—Bending Modulus (GPa) | 0.48 | 0.02 | 4.16 |
Hat core—Bending Modulus (GPa) | 0.60 | 0.01 | 1.66 |
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Zaharia, S.M.; Pop, M.A.; Chicos, L.-A.; Buican, G.R.; Lancea, C.; Pascariu, I.S.; Stamate, V.-M. Compression and Bending Properties of Short Carbon Fiber Reinforced Polymers Sandwich Structures Produced via Fused Filament Fabrication Process. Polymers 2022, 14, 2923. https://doi.org/10.3390/polym14142923
Zaharia SM, Pop MA, Chicos L-A, Buican GR, Lancea C, Pascariu IS, Stamate V-M. Compression and Bending Properties of Short Carbon Fiber Reinforced Polymers Sandwich Structures Produced via Fused Filament Fabrication Process. Polymers. 2022; 14(14):2923. https://doi.org/10.3390/polym14142923
Chicago/Turabian StyleZaharia, Sebastian Marian, Mihai Alin Pop, Lucia-Antoneta Chicos, George Razvan Buican, Camil Lancea, Ionut Stelian Pascariu, and Valentin-Marian Stamate. 2022. "Compression and Bending Properties of Short Carbon Fiber Reinforced Polymers Sandwich Structures Produced via Fused Filament Fabrication Process" Polymers 14, no. 14: 2923. https://doi.org/10.3390/polym14142923
APA StyleZaharia, S. M., Pop, M. A., Chicos, L.-A., Buican, G. R., Lancea, C., Pascariu, I. S., & Stamate, V.-M. (2022). Compression and Bending Properties of Short Carbon Fiber Reinforced Polymers Sandwich Structures Produced via Fused Filament Fabrication Process. Polymers, 14(14), 2923. https://doi.org/10.3390/polym14142923