On the RTM Infiltration of Fiber Reinforced Composites made by Tailored Fiber Placement

Abstract

Tailored Fiber Placement (TFP) is a preform manufacturing process, in which rovings made of fibrous material are stitched onto a base material, increasing the freedom for placement of fibers. Due to the particular kinematics of the process, the infiltration of TFP preforms with Resin Transfer Molding (RTM) is sensitive to multiple process and material parameters, like injection pressure, resin viscosity, and fiber architecture. An experimental study is conducted to investigate the influence of TFP manufacturing parameters on the infiltration process. A transparent RTM-tool that enables to visually track the resin flow front was developed and constructed. Microsection evaluations were produced to observe the thickness of each part of the composite and evaluate the fiber volume content of the part. Qualitative results have shown that the infiltration process in TFP structures is strongly influenced by a top and bottom flow layer. The stitching points and the yarn also create channels for the resin to flow. Furthermore, the stitching creates some eye-like regions, which are resin-rich zones and normally not taken into account during the infusion of TFP parts.