Fabrication of T-Shaped Structural Composite through Resin Transfer Molding

Abstract

Resin transfer molding (RTM) combines resin impregnation and composite fabrication in one process. It simplifies the process for composite fabrication and has the advantages of automation, low cost, and versatile design of fiber reinforcements. The RTM process was used in this study to fabricate T-shaped stuctural composites. Edge effects due to the gap between the fiber mats and the mold or the imperfect sealing of the matting mold resulted in edge channeling flows, leading to dry spot enclosure in the composite. It was found that a vacuum in the mold cavity could reduce the size of the dry spot. Proper control or prevention of the edge flows will reduce the possibility of dry spot formation. Numerical simulations of the mold filling were conducted to study the effect of gate locations on the mold filling patterns and edge channeling flows. Mechanical pulling tests were conducted to investigate the joint strengths of the T-shaped structure for different fiber materials. Fiber stitching on the rib provided an improvement in the joint strength while different fiber materials without fiber stitching tended to have the same joint strengths.