Document Type
Article
Publication Date
2025
DOI
10.3390/fib13110145
Publication Title
Fibers
Volume
13
Issue
11
Pages
145
Abstract
Fiber tow-gaps and overlaps formed during the Automated Fiber Placement (AFP) process pose a significant challenge by introducing non-uniform composite morphologies, often characterized by resin-rich regions and fiber waviness. These defects occur as deposited fibers sink into the gap regions during consolidation, with gap geometry determined during path planning. Such morphological inconsistencies can compromise structural reliability by initiating premature failure, particularly through localized out-of-plane waviness and resin accumulation. This study investigates the integration of high melting temperature thermoplastic veils, specifically polyetherimide (PEI), into fiber tow-gaps as a method to prevent ply sinking and reduce fiber waviness on both internal and external surfaces of the laminate. The PEI veils also serve to reinforce resin-rich regions by forming an interpenetrated network of high fracture toughness material within the brittle epoxy matrix. Tensile tests conducted on cross-ply laminates containing staggered gaps demonstrated that the inclusion of PEI veils modified the failure mode. The results suggest that the selective placement of thermoplastic veils within tow-gaps during AFP offers a viable strategy to mitigate manufacturing-induced non-uniform morphologies.
Rights
© 2025 by the authors.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International (CC BY 4.0) License.
Data Availability
Article states: "The data presented in this study are available on request from the corresponding author."
Original Publication Citation
Ravangard, A., Celebi, K., Kravchenko, S. G., & Kravchenko, O. G. (2025). Mitigating out-of-plane fiber waviness in AFP laminates with tow-gaps via selective placement of thermoplastic veils. Fibers, 13(11), Article 145. https://doi.org/10.3390/fib13110145
ORCID
0009-0005-9054-3168 (Ravangard), 0000-0002-8573-7540 (Kravchenko)
Repository Citation
Ravangard, Ahmadreza; Celebi, Kuthan; Kravchenko, Sergii G.; and Kravchenko, Oleksandr G., "Mitigating Out-of-Plane Fiber Waviness in AFP Laminates with Tow-Gaps via Selective Placement of Thermoplastic Veils" (2025). Mechanical & Aerospace Engineering Faculty Publications. 190.
https://digitalcommons.odu.edu/mae_fac_pubs/190
Included in
Aerospace Engineering Commons, Industrial Engineering Commons, Materials Science and Engineering Commons