The structure-permeability relation of textile reinforcements

The limits of production processes of composites are explored increasingly. A higher performance and a higher quality are demanded at lower cost prices. Inevitably, a thorough understanding of the processes occurring during the production is essential to meet the imposed demands. The research presented here aims to increase the fundamental knowledge on a crucial part of the Resin Transfer Moulding (RTM) production technology: the impregnation behaviour of textile reinforcements. In RTM, a near-net-shaped, dry, textile preform is manufactured and placed in a closely fitting mould. Resin is subsequently injected, typically at a pressure varying between 2 and 10 bars relative to the atmospheric pressure. The textile reinforcement is made of a fibre bundle structure, which can either be a preform made of (a stack of) woven fabrics or Non¿Crimp Fabrics (NCF), or be a preform manufactured employing automated preforming technologies such as braiding and fibre placement technologies.