Research on Curing Condition of SMC Roll Forming: Effects of the Thermal Expansion on the Thickness of the Products

摘要

We have attempted to apply roll forming to SMC. SMC roll forming has some advantages compared with other molding method, which are a lower forming energy, a short production time, a controllability in fiber orientation, a possibility for long-sized products and so on. Until now, setting of the forming condition and deformation characteristics has been established in the forming process. In the roll forming with the aim of continuous molding, the establishment of curing condition and the explication of cure characteristics is to be very useful. However, the study in the curing process has not been carried out. Then, in order to investigate the characteristics we carried out the experiments about tensile strength and elastic modulus. Next, the material temperature was investigated in order to grasp the material condition in the each timing, when the reduction added. Finally, we searched the condition of restraining the expansion of products. We obtained the following results. When the expansion of the thickness is restrained, the density increases, and the value of tensile strength and elastic modulus increases. And, we can predict the exothermic reaction start time and the curing completion time. In addition, strength can be increased, the expansion of the thickness is restrained before the exothermic start time. Then, we have aimed at the establishment of the molding method with the reliability in SMC roll forming.