Improved Manufacturing Technologies for Polymer Matrix Composite Engine Components

The recent development of AFR-PE-4E polyimide composites has increased the high-temperature performance of military engine structures due to weight reduction. In order to take full advantage of this “new” composite system, and to compete against titanium, low-cost manufacture of AFR-PE-4E resin and prepreg must be achieved. Current F135 and F136 engines slated for the Joint Strike Fighter (JSF) require ducts that total up to 300 pounds per engine. AFR-PE-4E composite has currently been selected for these structures which will require continuous service temperatures in excess of 316ºC (600ºF) while retaining maximum physical strength. The high cost of AFR-PE-4 resin is primarily driven by the high cost of the 4-PEPA and 6FDA monomers. Reducing the AFR-PE-4E resin cost can be realized through obtaining alternate monomer sources. The major goal of the Phase II SBIR program is to identify a combination of lower cost monomer suppliers and demonstrate their suitability through fabrication of carbon fabric prepreg trial lots and discriminator panels. Chemical characterization and physical mechanical testing is planned to provide a thorough assessment of batch-to-batch reproducibility, storage stability, and reactive behavior. The thermal performance, processing characteristics, and cost benefits will be determined and compared to the baseline AFR-PE-4E material.