PhD's

dr. ir. Edwin Lamers

ctw/pt

PhD Project:

Shape distortions in fabric reinforced composite products due to processing induced fibre reorientation

Defence:

23rd of april 2004

Partners:

Part of the project related to the thermosetting matrix was performed within the framework of Brite Euram project ‘Precimould’. The part related to rubber pressing was performed with Stork Fokker and Ten Cate Advanced Composites within the project ‘Precision Rubber Pressing’ sponsored by the Netherlands agency for aerospace programmes NIVR.

Summary:

Shape distortions occur during manufacturing of composite products. These distortions often exceed the high dimensional accuracy required in the aeronautical industry. Costly trial and error methods are generally applied to meet the dimensional accuracy. Modelling the shape distortions on beforehand can aid reduce the development costs of these products.

In this work, the objective is to model the shape distortions during rubber pressing using a FE method with computationally effective plate elements.


First, the fibre reorientation during processing of single- and multi-layered biaxial woven fabric composites is predicted. A material model accounts for the intra- and inter-ply shear behaviour of these composites. As confirmed by rubber-pressing experiments, this so-called drape model predicts a clear dependency between the drape-ability and the lay-up of multi-layered composites.

Secondly, products distortions are predicted, accounting for the locally changed composite properties due the fibre reorientation predicted in the first step. A micromechanical model of the weave considered is used for this purpose.


figure 1: Fibre reorientation of the double dome geometry for different lay-up


The results of the model are validated on the shape distortions of a woven fabric reinforced thermoplastic composite with a double dome geometry. Additionaly, the shape distortions of a hemispherical product and a wing leading edge stiffener are demonstrated.


figure 2: Deformed mesh of an hemispherical product after cooling.


Related research:

­Akkerman R., R.S. de Vries, Thermomechanical properties of woven fabric composites, International Conference on Fibre Reinforced Composites FRC'98, A.G. Gibson (editor), Woodhead publishing limited, ISBN 1855733751, 1998, p. 422 - 429

­S. Wijskamp, Shape Distortions in Composites Forming, PhD thesis University of Twente, 2005, ISBN 90‑365‑2175‑0.

Publications:

­E.A.D. Lamers, S. Wijskamp & R. Akkerman, Modelling the distortions of skewed woven fabric reinforced composites, in: Proceedings of TexComp 5, the 5th International Conference on Textile Composites, 18-20 September (2000), Leuven, Belgium.

­S. Wijskamp, E.A.D. Lamers & R. Akkerman, Spring-forward of woven fabric reinforced composites, in: Proceedings of TexComp 5, the 5th International Conference on Textile Composites, 18-20 September (2000), Leuven, Belgium.

­E.A.D. Lamers, S. Wijskamp & R. Akkerman, Modelling the thermo-elastic properties of skewed woven fabric reinforced composites, ECCM 9 (2000), Brighton, UK.

­S. Wijskamp, E.A.D. Lamers & R. Akkerman, Effects of out-of-plane properties on distortions of composite panels,in: Proceedings of Fibre Reinforced Composites 2000, editor A.G. Gibson,Woodhead Publishing Ltd.,2000 p.361-368.

­E.A.D. Lamers, R. Akkerman & S. Wijskamp, Drape Modelling of Multilayer Fabric Reinforced Thermoplastic Laminates, Texcomp-6 conference Philadelphia(PA), 2002.

­E.A.D. Lamers, R. Akkerman & S. Wijskamp, Orientation Modelling for Rubber Press Forming of Thermoplastic Laminates, International Journal of Forming Processes, 2002, p.443-463.

­E.A.D. Lamers, R. Akkerman & S. Wijskamp, Fibre Orientation Modelling for Rubber Press Forming of Thermoplastic Laminates, 5th ESAFORM conference Krakow (Poland),2002 , p.323-326.

­S. Wijskamp, E.A.D. Lamers, R. Akkerman & E.C. van de Ven, Warpage of rubber pressed composites, ECCM 10, Brugge (Belgium), 2002.

­S. Wijskamp, E.A.D. Lamers & R. Akkerman, Residual stresses in rubber formed thermoplastic composites, 6th ESAFORM conference, Salerno (Italy), 2003, p.855-858.

­S. Wijskamp, R. Akkerman & E.A.D Lamers, Residual stresses in non-symmetrical carbon/epoxy laminates, ICCM-14, San Diego (USA), 2003

­E.A.D. Lamers, S. Wijskamp & R. Akkerman, Drape Modelling of Multi-Layered Composites, 6th ESAFORM conference Salerno (Italy), 2003, p.823-826.

­E.A.D. Lamers, S.Wijskamp, R. Akkerman, Modelling shape distortions in composite products, 7th ESAFORM Conference, Trondheim, 2004.

­S. Wijskamp, E.A.D. Lamers and R. Akkerman, Spring-forward in composite plate elements, in: Proceedings of the 8th Esaform Conference on Material Forming, Cluj-Napoca (Romania), 2005, p.943-946.

­

­E.A.D. Lamers, Shape Distortions in Fabric Reinforced Composite Products Due to Processing Induced Fibre Reorientation, PhD thesis University of Twente, 2004, ISBN 90‑365‑2043‑6.

Now:

Edwin lamers joined Reden in the Netherlands (www.reden.nl)