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Title: Numerical Evaluation of Reinforcement Morphology Contribution to Process-Induced Residual Stresses in 3D Woven Composites
3D woven composites, in particular carbon/epoxy, are being increasingly adopted in aerospace, wind energy, transportation and other industries due to their high strength, lightweight, good dimensional stability and delamination resistance. They are often produced by resin transfer molding with epoxy cured at elevated temperature. This process can result in high level of residual stresses due to the mismatch in thermal expansion coefficients of carbon and epoxy. In this paper, a numerical modeling in combination with blind hole drilling experiments is utilized to determine processinginduced residual stresses in 3D woven composites using the example of orthogonal reinforcement. In particular, the individual contributions of residual stress in the weft and binder tows as well as resin-rich pockets to the entire residual stress distribution are evaluated. Our studies show that these contributions are determined by both arrangement and orientation of the tows. The developed numerical modeling tool can be used in the design of reinforcement architectures with reduced levels of residual stresses.  more » « less
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Proceedings of NUMIFORM 2019: The 13th International Conference on Numerical Methods in Industrial Forming Processes
Medium: X
Sponsoring Org:
National Science Foundation
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