Improvement of impregnation quality on out-of-autoclave processed CFRP aircraft wing spar through resin flow simulation

Abstract

Vacuum-assisted resin transfer molding (VaRTM) is becoming one of the most robust alternatives for autoclave processes. VaRTM, which applies the resin injection method in a vacuum environment, generally uses fiber reinforcement and a polymer matrix separately in the process. The VaRTM is mainly dominated by the characteristics of constituent materials, such as preform permeability and resin viscosity. Among them, process design with the arrangement of resin inlet/outlet locations is closely related to process defects, and inappropriate inlet/outlet layouts cause voids, etc, which has a decisive effect on quality degradation. Therefore, in this study, a highly curved and twisted spar structure was fabricated by the VaRTM, and both flow simulations using Programs for Applied Mechanics–Resin Transfer Molding software and experimental test parts built with three different inlet/outlet line conditions were performed and compared to predict and improve impregnation quality. There was good agreement between the simulation and built test specimen for the three cases that the shorter inlet and outlet length resulted in improved impregnation quality. It was verified that impregnation and inner quality could be improved through flow simulation analysis during the VaRTM process.

Environmental Impact of an Innovative Aeronautic Carbon Composite Manufactured via Heated Vacuum-Assisted Resin Transfer Molding

“…The most common OoA processes are vacuum bagging, oven cure, VARTM, quickstep curing, resin film infusion, and resin infusion under double-flexible tooling [5]. Of all of these processes, VARTM is one of the most robust and attractive replacements for autoclave processes [6]. VARTM is a closed-mold process that places dry reinforcements into a mold, seals them with a sealed flexible membrane (vacuum bag), and then, using differential pressure, infuses resin and impregnates the dry fibers.…”

Effect of dynamic friction and static friction in finite element analysis of carbon fiber preform

“…To analyze this process, the preform was simulated through several simulators, and various studies were conducted according to the type and direction of the fiber based on the shape. [8,9] The Boisse group proposed a 3D continuous model considering the local stiffness to simulate the 3D textile of the composite fiber preform, improving the curvature and internal load. The preform was then analyzed, and an improved draping simulation was suggested.…”

Characterization of the tensile behavior of continuous carbon fiber reinforced polyamide 6 under self‐resistance electrical heating

“…[10,11] There are many methods to manufacture fiberreinforced polymer (FRP) components [12][13][14] including winding molding, [15] resin transfer molding, stamping molding and the like. [16][17][18] Stamping molding is one of the most commonly employed methods to fabricate CFRT component in automobile manufacturing industry due to its low cost and short production cycle. For stamping molding process, it has several stages.…”