A macroscopic approach to simulate the forming behaviour of stitched unidirectional non-crimp fabrics (UD-NCF). (November 2017)

• Record Type: Journal Article
• Authors: Schirmaier, F.J.; Dörr, D.; Henning, F.; Kärger, L.
• Is Part Of: Composites. Volume 102(2017)
• Page Start: 322
• Page End: 335
• Publication Date: 2017-11
• Subjects: Composite materials -- Periodicals; Manufacturing processes -- Periodicals; Composite materials; Manufacturing processes; Periodicals; 620.11805
• DOI: 10.1016/j.compositesa.2017.08.009
• Languages: English
• ISSNs: 1359-835X

Abstract

Abstract: Thin composite shell structures manufactured from stitched unidirectional non-crimp fabrics (UD-NCF) in a liquid composite moulding process provide high lightweight design capabilities. For complex geometries, the forming process of the textile pre-products is challenging and requires intensive investigations to avoid defects like macroscopic wrinkling or fibre gapping. In contrast to biaxial engineering fabrics, UD-NCF has been investigated only sparsely in terms of its forming behaviour, both experimentally and numerically. To close this gap, a macroscopic forming simulation model for UD-NCF is proposed in this work, including a new non-orthogonal and linear strain measure for large strains and the corresponding nominal stress measure. To parameterize the constitutive laws and to investigate the multiaxial deformation behaviour of UD-NCF, supplementary off-axis-tension tests with optical strain measurement are performed in this work. The new forming simulation model is validated via forming simulation of a hemisphere test and of a preforming process of an automotive component.