The advantages of using Non-Crimp Fabric (NCF) in structural automotive applications over traditional woven reinforcements are now widely accepted. NCFs commonly need to be formed into complex shapes during composites manufacturing, which can lead to defects in the fabric structure. These mechanisms are often different to those seen in traditional woven reinforcement due to the presence of intra-ply stitches, which are used to constrain the UD tows. Stitches have been selectively removed in this work in various locations to understand their influence on forming quality. Grid strain analysis has been used to calculate local shear angles and strain, in order to understand defect initiation. Results from this study have shown that it is possible to reduce the severity of defects by choosing appropriate locations for stitch removal. In addition, an explicit finite element model has been developed to describe the forming behaviour of NCF and to capture the effects of stitch removal.
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