Curved beam strength and toughness of thin ply cfrp non crimp fabric laminates

2015-09-12
Arca, Miray
Papila, Melih
Çöker, Demirkan
Carbon fiber reinforced plastics are most widely used composite materials in aerospace and wind turbine industries. Their superior in plane properties with light weight structures and also ability to change and design the structure and form make composites preferable to metallic materials. Composites are applied to the primary load carrying members with complex and curved geometries with the new manufacturing techniques. On the other hand, failure mechanisms of composites are different and complicated than the metallic structures. Out of plane properties of composites are not as good as in plane properties, unbalanced properties of reinforcement and matrix and radial geometry of the curved part creates weakness through the thickness direction leading to delamination failure. In this study effect of novel material-thin ply non crimp fabric laminates on delamination resistance of carbon fiber reinforced plastics composites are presented. For this purpose standard test methods are carried out, fracture toughnesses and behavior of laminates under moment loading are obtained experimentally. The dynamic delamination propagation and failure sequences are captured using Photron© Fastcam SA5 ultra high speed system. Changing the material type from unidirectional to thin-ply non-crimp fabric material increased the mode I, mode II fracture toughness and curved beam strength of the laminates. It is observed that the manufacturing defects are the potential failure initiation sides.
8th Ankara International Aerospace Conference, 10 - 12 September 2015

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Citation Formats
M. Arca, M. Papila, and D. Çöker, “Curved beam strength and toughness of thin ply cfrp non crimp fabric laminates,” presented at the 8th Ankara International Aerospace Conference, 10 - 12 September 2015, Ankara, Turkey, 2015, Accessed: 00, 2021. [Online]. Available: http://aiac.ae.metu.edu.tr.