APPLICATION OF SCIENCE-BASED RTM FOR FABRICATING PRIMARY AIRCRAFT STRUCTURAL ELEMENTS

Resin Transfer Molding (RTM) technology is being developed by the NASA Langley Research Center under the Advanced Composites Technology (ACT) program as a cost-effective method for fabricating primary aircraft structures. Challenges lie in successfully infiltrating large, skin/stiffener textile preforms using hot, reacting resins. RTM variations include resin film infusion (RFI) and pressure injection (PI). This paper describes the program which includes modeling, dielectric sensing, model verification, and applications. Preform compaction and permeability measurements are described Resins are characterized using differential scanning calorimetry (DSC) and rheometry Darcy's law continuity equations, and finite element techniques are used to model the flow. Models are verified with data taken by conventional temperature and pressure sensors, and by dielectric sensors for flow front position, viscosity, and eye monitoring.