Resin Film Infusion Process: Numerical Algorithm

Abstract

The liquid composite molding (LCM) belongs to the composite manufacturing processes. In this family, a fabric preform material is placed into the mold cavity, and then it is impregnated with a thermosetting resin of low viscosity, until the fiber skeleton is entirely filled and finally polymerized to create a polymeric composite product. Due to its advantages, LCM has gained attention and competitiveness against other composite manufacturing processes. The resin film infusion (RFI) belongs to the LCM family, but unlike the other variants, such as resin transfer molding (RTM) and vacuum assisted resin infusion (VARI), in which the liquid resin is injected or infused into the mold cavity, the resin in the RFI process is placed into the mold cavity in the semi-cured state. Then, under pressure and temperature, the resin film will be liquefied and impregnated the fibrous reinforcement in the thickness direction. This particularity permits to RFI to fabricate large complex composite structures and reduce significantly the equipment cost as compared to the conventional resin transfer molding processes. However, as this variant used only a vacuum bag as the upper half-mold, the fabricated part has non-uniformity in the thickness, low dimensional tolerances and low fiber volume fraction. The main objective of this paper is to propose a numerical algorithm allowing to study the influence of part thickness on the RFI’ filling time. Numerical simulation is based on the explicit finite difference method. The results obtained show that the filling time increases parabolically with the part thickness.