Polymer/carbon pin through thickness reinforcement

This work discusses the development and refinement of a polymer/fibre through thickness reinforcement method. Similar in initial concept to the traditional metalworking process of riveting this allows the manufacture of through thickness reinforced 2-D preforms. Pins are placed with deliberate excess length using a veterinary needle to part in-plane fibres. A lay-up with an array of pins is then subjected to a hot-press process flattening the pin ends resulting in a consolidated preform. This preform exhibits useful characteristics such as the ability to be cut and reformed to a new topology, with the through thickness reinforcement also conforming to the new shape. Refinements to the process introduce a multi-stage press process aimed at improving pin orientation with both original and refined processes evaluated using ASTM D5528 to determine the effect on interlaminar fracture toughness.