Abstract

Carbon fiber reinforced thermoplastics are gaining interest because of the advantages such as short cycle times, toughness, and recyclability. The composite parts can be produced from thermoplastic composite sheets, also known as organo-sheet by stamp-forming technology. A double-belt press is one of the solutions for organo-sheet production. The machine consists of heat and pressure modules for impregnation and a subsequent cooling module for solidification, enabling a continuous compression molding process. There are two types of press systems for a double-belt press, the isobaric press, and the roller press. The roller press system is more versatile for various kinds of composites There are several fixed rollers in the heating zone on both the upper and lower sides where the minimum gaps can be controlled between the belts. The pressure is not constant under rollers, which depends on the materials and process conditions. Therefore, the understanding of the combined behavior of the fabric compaction, resin impregnation, and resin in-plane flow under a roller is inevitable to optimize the process parameters for the efficient impregnation in double belt press. In this study, we have developed a simplified simulation model to investigate the impregnation process under a roller in double belt press using PAM-COMPOSITES® software (ESI group). The model consists of a fabric layer, a resin layer, and an inclined steel belt. The software utilizes fluid-solid mechanics coupling to determine the fabric compaction and can handle the vanishing gaps between the steel belts during the impregnation process. We have studied the influences of process parameters on the pressure profiles, impregnation, and resin in-plane flow using this simulation. Furthermore, we have conducted the experiments using double belt press and compared the results with the simulation results. The results will be helpful to optimize the effective impregnation process for organo-sheet production using double belt press system.