EXPERIMENTAL DETERMINATION OF PREFORM PERMEABILITY VARIATION WITH POROSITY FOR FIBERGLASS AND CARBON MATS

摘要

This paper presents the results of experimental investigation on fiber bed permeability variation with porosity for woven carbon and fiberglass mats. Resin flow experiments were performed in a rectangular cavity with different fiber volume fractions. RL 440 epoxy resin was used as the working fluid in the experiments. Several layers of plain-weave fiberglass and carbon fiber mats were used as reinforcements. The effects of reinforcement type, and porosity on fiber bed permeability were investigated. Fiber mat permeability of woven mats showed large degrees of anisotropy. Preform permeability showed a nonlinear increase with fiber bed porosity for both types of fiber mats. At the same preform porosity, permeability of fiberglass fiber bed was measured to be about six times that of carbon fiber mats. The results of this investigation could be employed in manufacturing process optimization in liquid composite molding.