EXPERIMENTAL INVESTIGATION OF THE DRAPING PROPERTIES OF REINFORCEMENTFABRICS

The draping behaviour of some fabrics commonly used in resin-transfer moulding processes has been examined. The aim of the initial part of t his study was to investigate test methods for determining shear proper ties. The bias extension and simple shear test methods were compared, and the effects of aspect ratio and boundary conditions were also exam ined. The results showed considerable differences when different test methods, aspect ratios and boundaries were used. A means of eliminatin g boundary-condition effects and obtaining a true stress/strain relati onship is indicated. Investigation of yarn slippage was also one of th e major concerns in this study. Yarn slippage was found to be affected by non-uniformity of deformation,, boundary conditions and difference s in fabric materials. Tensile and out-of-plane bending tests were con ducted. The shear and tensile stress/strain relationships were modelle d. The test results also provide the thickness change during shear, un loading behaviour, bending rigidity and the effect of wet-out on the m aximum shear angle. (C) 1998 Elsevier Science Ltd, All rights reserved .