Influence of Reinforcing Layer Orientation on Impact Response of Plain Weave RTM Composites

Abstract

Two-dimensional fabric forms such as plain weaves are increasingly being considered as the reinforcement of choice for large composite structures ranging from ballistic panels and tank hulls to marine and offshore structural components. A number of these are subject to out-of-plane impact. This paper addresses the influence of stacking sequence on resistance to static and low velocity dynamic penetration. A series of seven layer 24 oz. plain weave E-glass reinforced vinyl-ester composites were manufactured using the RTM process and their response was investigated through static and low-velocity impact testing. Inelastic Energy Curves were used in conjunction with measured projected damage areas and fiber bundle fractures to describe the dynamic behavior. Static and dynamic resistance to penetration is seen to increase with a non-zero delta between adjacent fabric layers. Trends observed during static testing compare well with dynamic behavior and the type of damage observed is similar. Final puncture depends predominantly on the number of fiber bundles fractured or pushed aside to provide a path for penetration.