New publication on the effect of in-plane fiber waviness defects
TPRC researcher Ramona Sitohang published "Effect of in-plane fiber waviness defects on the compressive properties of quasi-isotropic thermoplastic composites" in Composite Structures.
Manufacturing sometimes leads to defects such as fiber waviness in thermoplastic composite parts. The influence of in-plane fiber waviness defects on the compressive properties of quasi-isotropic (QI) C/PEEK laminates was investigated in this article. Compression tests coupled with high-speed camera monitoring were performed to study the failure process. It was confirmed that the waviness defects act as a trigger for the initiation of damage resulting into an early failure.
Fig. 1. In-plane waviness defects in an L-shaped stamp-formed QI C/PEEK composites part.
Fig. 2. High-speed camera footages of the side of the QI1 specimen with waviness.
In general, it was found that local waviness has a negligible effect on the global laminate stiffness, but that the severity of waviness was such that the ultimate compressive strength of the QI laminate drops proportionally to the percentage of plies oriented in the loading direction that is wavy.
The research was conducted by TPRC in collaboration with the University of Twente. The financial support from the Province of Overijssel for improving the regional knowledge position within the Technology Base Twente initiative is gratefully acknowledged. Feel free to contact us for more information on this or other subjects in thermoplastic composite technology.