SBIR-STTR Award

Braiding machinery can be adapted to produce low cost, high permance composite parts. Fiber impregnation has been a limiting factor in the usefulness of braiding. Preimpregnated fibers are expensive and braid poorly because of the resin tack. The proposed resin applicator ring will provide continuous impregnation with low cost i liquid resins during braiding with no reduction of braiding speed and no limitations in part geometry. Cost savings are expected to be 12-3 2 percent compared to parts made with preimpregnated yarns. Additional benefits may include greater versatility lower tooling costs, simpler cure cycles, and shorter lead times. The purposes of this phase i proposal are to obtain experimental verification of the applicator ring concept. To develop a simple computer program to facilitate production using the applicator ring, and to compile needed data on available resins and fibers

Phase i research has demonstrated the basic ability of the resin applicator concept to impregnate moving fibers in a controlled fashion. Phase ii research is proposed to develop a full scale composite braiding system using this concept. Major objectives of phase ii work are to test the effects of scale-up, 360 deg fiber orientation, performance in biaxial and triaxial braiding, and production procedures. Problems with flow control of viscous epoxies experience in phase i will be addressed. Testing of basic mechanical properties, resin content and void content will be conducted on parts braided with the prototype resin applicator system. A two step approach is proposed: first, a sub-scale prototype will be built and tested at u.s. composites. A full-scale production resin applicator ring will then be built and installed on a 144 carrier braider at watervliet arsenal's composite laboratory. Operational testing will be performed over a five month period.