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This paper deals with numerical modelling of the mechanical behaviour of short fibre reinforced plastic composites manufactured by the injection moulding process. First of all, an experimental program has been carried out in which the local fibre orientation distribution has been measured in an 80x80x2mm injected plate by means of polished cut sections, analysed with SEM and image processing software. Tensile and three-point bending tests have been performed to obtain the elastic and strength response of the material in different locations along the plate and at two directions (parallel and normal to the flow direction). Analytical micromechanical models and averaging procedures have been implemented to relate the local fibre orientation distribution with the effective local anisotropic response of the material (elastic and strength). The models are validated by means of the finite element simulation of the performed characterisation tests. Finally, the methodology is applied to an injection moulded component with complex geometry. Fibre orientation data predicted with mould-flow software has been used to determine the local effective elastic stiffness and strength coefficients. A FE simulation of the functional behaviour of the component has been carried out. Results indicate that the proposed variable stiffness/strength anisotropic model predicts a lower load for onset of failure than when applying an equivalent isotropic material model.

The out-of-plane permeability of two glass fibre fabrics was measured by 26 institutions using silicone oil as a test fluid. Participants in this study were free to select the test procedure, specimen dimensions and data analysis method, provided that testing was carried out at three target fibre volume fractions, 46 %, 50 % and 54 %. While results showed a variability of two orders of magnitude between participants, most values were within a significantly narrower band. A majority of participants used 1D saturated test method. A few selected 1D unsaturated and 3D unsaturated flow method which gave very similar results. Focusing on analysis of data and results of 1D saturated flow measurements, results are not conclusive, but they are consistent with number of layers in a specimen, fibre volume fraction, injection pressure and sealing of specimen edges all having an effect on the measured permeability. Specifying limits for these parameters is expected to result in reduced scatter in measured permeability., Composites Part A: Applied Science and Manufacturing, 148, ISSN:1359-835X, ISSN:1878-5840