Enhancement of resin transfer molding using articulated tooling

Mold articulation is introduced in this concept for resin transfer molding (RTM) to increase mold fill times and potentially allow for the use of high viscosity, hot melt resin systems, or thermoplastics. Following a brief review of conventional RTM and a discussion of the limitations on the factors that control fluid flow through porous media, the articulated concept is described. This is followed by an explanation of the sequence of motion of an articulated segmented mold necessary for consolidation, void removal and accelerated fluid flow through a fibrous preform. An analysis of the process using a fiber preform with orthotropic permeability is outlined from which mold fill time is obtained. This is compared with conventional RTM mold fill times using typical resin properties and fiber volume fractions. For the conservative assumptions used, an improvement by a factor of ten in mold fill time is achieved using the articulated process relative to conventional RTM.