Manufacturing process and performance of dry carbon fabrics reinforced with rectangular and circular z-pins

Composite materials possess high mechanical in-plane properties but suffer from very low out-of-plane properties due to limited inter-laminar strength. Common z-pinning techniques to improve the mechanical properties of composites materials are presented in this paper. Special techniques to reinforce liquid composite molding preforms are explained. A new, low-cost z-pinning method to create high-performance laminates of dry fabrics invented by the author will also be introduced. Mode I double cantilever beam tests are performed to compare rectangular and circular z-pins using the newly described manufacturing process.