Abstract
VaRTM process impregnates resin to fiber preform using difference in pressure between atmosphere and vacuum, and attracts attention as a method to mold FRP at relatively low cost. However, resin impregnation behavior in the fiber preform is not understood exactly, and the formation of voids during the process is a problem to be avoided. It is said that a distribution medium which is incorporated on the fiber preform as a surface layer has a significant effect on resin impregnation behavior. In this study, multipoint measurements for resin flow during VaRTM process are carried out by using embedded fibre optic sensors. By simultaneously infusing epoxy resin into two glass fibre preforms with or without a distribution medium that are separated by a plastic film, resin amount impregnated through in-plane flow and out-of-plane flow via the distribution medium are compared. It has been found that resin amount impregnated through the out-of-plane flow via the distribution medium is found to be dominant, especially for thinner fiber preform. In addition, numerical calculation for resin impregnation during the VaRTM process was also carried out. The simulated resin amount impregnated via the distribution medium agreed well with the experimental results.
