Resin pressure variation in prepreg stack during thermal expansion process with silicone rubber

A thermal expansion process with silicone rubber was adopted to prepare carbon fiber/bismaleimide resin composite laminates. By means of a designed processing mold and a resin pressure online measuring system, the thermal expansion pressure and the resin pressure in the prepreg stack during the process were measured and analyzed. The effects of the process gap and temperature distribution were investigated, and the consolidation degrees of cured laminates under different process conditions were studied using the micrographs of laminates. The results show that the resin pressure in prepreg stack during thermal expansion process can be measured using the resin pressure online measuring system. The process gap and the temperature distribution inside the silicon rubber strongly influence the resin pressure and the thermal expansion pressure. When the process gap is reasonable, the trend and the variation degree of the thermal expansion pressure and the resin pressure before gelation are almost consistent in zero-bleeding process. The cured laminates are compact with uniform thickness. By adding the temperature platform to reduce the temperature distribution inside the silicone rubber, the increasing speed of thermal expansion pressure can be decreased.