Investigation of the matrix influence on the laminate properties of epoxy- and polyurethane-based CFRPs manufactured with HP-RTM-process

The high pressure resin transfer molding (HP-RTM) process has the potential for high-volume production of continuous fiber-reinforced components in the automotive industry. The development of robust equipment, new process variants and highly reactive matrix systems lead to significant reductions of the cycle time in recent years. The paper addresses the manufacturing of carbon fiber reinforced plastic (CFRP) laminates using different matrix systems. To evaluate the matrix influence on the material properties, matrix dominated test methods were selected for evaluation of the mechanical properties. The test plates were made with the HP-RTM process at constant process parameters using carbon fiber fabrics. Only the matrix-specific supplier instructions for processing of the matrix systems (mixing ratio, temperature of components in HP-RTM equipment and mold) were varied in the study. Three Polyurethane (PU) systems and one Epoxy (EP) system were used for the characterization of the matrix dominated properties. To identify the interlaminar shear properties, two test methods were selected and compared to each other: The Short-Beam Shear (SBS) Test and the Edge Shear Test (ESH). To obtain the damage tolerance under impact loading, the energy absorptions for each material combination during instrumented drop tower tests were investigated. The results show the impact of the different Epoxy and Polyurethane matrix systems on the laminate performance.