Intra-ply shear is an important mechanism in thermoforming processes of UD fibre reinforced thermoplastic laminates. Various methods have been developed to characterise this shear mechanism, but measured properties differ for several orders of magnitude. The potential of another technique is shown in this paper. This approach considers a strip with a rectangular cross section, subjected to torsion. Several analyses have been carried out to determine the significant material properties for this loading mechanism. For clarity, isotropic and orthotropic elastic material behaviour was considered first. The response torque mainly depends on the in-plane shear modulus G12. An extension was made to the analysis of anisotropic viscous material behaviour. Closed form solutions and FE simulations were compared, using a fibre reinforced viscous fluid model. The torsional response of a partially clamped strip was highly influenced by the fibre stiffnesses. Nevertheless, it is possible to relate the longitudinal viscosity to a closed form solution directly, if bulging is not suppressed and constant through the length of the strip. A smart clamping design is therefore required.
|Publication status||Published - 11 Jul 2010|
|Event||10th International Conference on Flow Processes in Composite Materials, FPCM-10 2010 - Monte Verita, Ascona, Switzerland|
Duration: 11 Jul 2010 → 15 Jul 2010
Conference number: 10
|Conference||10th International Conference on Flow Processes in Composite Materials, FPCM-10 2010|
|Period||11/07/10 → 15/07/10|
- Intra-ply shear
- Rectangular strip
Haanappel, S. P., ten Thije, R. H. W., & Akkerman, R. (2010). Constitutive modelling of UD reinforced thermoplastic laminates. 1-6. Paper presented at 10th International Conference on Flow Processes in Composite Materials, FPCM-10 2010, Ascona, Switzerland.