1996); Pages: xii + 297; Price: E99.00, Dfl225.00, US$ 159.00; ISBN 0 7923 3848 0.This book is volume 44 in the solid mechanics and its applications series published by Kluwer. It is a mathematical treatise embracing analytical and numerical methods suitable for solving crack problems. The approach presented is not based on finite element discretisation which, it is felt, leads to more approximate and computationally taxing solutions. In the work presented the crack geometry is somewhat idealised by comparison with finite element modelling which can achieve more realistic representations.

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a b s t r a c tResin infusion (a.k.a. VARTM) is one of the LCM processes, for which liquid resin is drawn into dry reinforcements. Significant cavity thickness changes occur during processing, due to the flexibility of the vacuum bag used as one side of the tool, and the complex stress balance within the laminate. While the magnitude of thickness change is often small, the influence is significant on reinforcement properties. Changes in permeability during filling and post-filling have the potential to significantly affect the process. To simulate this behaviour, it is important to accurately model compaction and unloading of reinforcement in dry and wet states. A series of tests were completed to determine compaction behaviour of an isotropic glass fibre mat. From these tests several non-linear elastic compaction models have been determined, and applied within a resin infusion simulation which addresses pre-filling, filling and post-filling. This simulation was then used to assess different post-filling strategies.

The resin infusion process (a.k.a. VARTM, SCRIMP) has developed as a low cost method for manufacturing large fibre reinforced plastic parts. This process still presents some challenges to industry with regards to reliability and repeatability, resulting in trial and error development being expensive and inefficient. This paper describes a fully instrumented resin infusion setup, providing preliminary experimental data acquired while varying influential parameters during the filling and post-filling stages. The laminate permeability is a strong function of the fibre volume fraction which can be determined from the laminate thickness. To assess the variation of the volume fraction and permeability, full field thickness variations have been monitored using a digital speckle stereophotogrammetry system developed for this purpose. In-mould resin pressures, flow front progression, and incoming resin flow rate were also measured. A selection of four experiments is presented here for discussion.

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