About this Abstract |
Meeting |
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Symposium
|
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Presentation Title |
Advances in Fiber Alignment Process for Highly Aligned Short Fiber Preforms for Thin Ply Composites |
Author(s) |
Navid Niknafs, John W. Gillespie |
On-Site Speaker (Planned) |
John W. Gillespie |
Abstract Scope |
Thin ply composites offer improvements in damage tolerance by increasing the tensile strain to initiate transverse microcracking in continuous fiber composite laminates. The incorporation of aligned short fibers in prepreg blanks provides enhanced formability through in-plane stretching in the fiber direction while providing mechanical properties comparable to continuous fiber composites at high fiber volume fraction (e.g. 57%). This study aims to create aligned short fiber composites in a thin ply format to enhance formability and damage tolerance. However, the major challenge is the high level of microstructural control of local fiber volume fraction and resin content required in the thin ply preform to achieve optimal mechanical properties. The recent development of Tailored Universal Feedstock for Forming (TuFF) wet-laid process provides a route for conducting experimental studies to improve microstructural control of the fiber alignment in preforms as low as 8gsm. Microstructural features include a high level of fiber alignment retention (95% distribution fall within 5 degrees of the axial direction) and spacing control between fibers, affecting local variations in fiber and resin content.
This study investigates advancements in TuFF preforms alignment for thin ply composites, addressing increased microstructural variability in 8gsm preforms. Machine learning image processing techniques are employed to characterize the microstructure of the material and identify mechanisms of fiber alignment imperfections, leading to the design and enhancement of short fiber alignment processes. Validation studies demonstrate improved material quality by minimizing windows between aligned fibers, resulting in thin ply composites with a more uniform microstructure. |
Proceedings Inclusion? |
Definite: Post-meeting proceedings |