Automated Through Thickness Reinforcement for Affordable & Robust High Temperature Composite Structures

The national imperative to field hypersonic weapon systems has increased the demand for robust, lightweight, and affordable high temperature materials for thermal protection systems.  Refractory composites such as carbon-carbon (C/C) or carbon/SiC (C/SiC) offer enormous promise, but wider-scale acceptance continues to be hindered by certain technical and affordability limitations.  Key among the technical limitations is the notoriously poor interlaminar strength properties of refractory composites.  There exist several proven technologies to increase interlaminar toughness in conventional polymer matrix composites, but their implementation in refractory composite systems has been hindered by technical difficulties and/or high cost.  New technical solutions for inherently expensive material systems such as C/C or C/SiC , regardless of the potential benefits, must address affordability first and foremost.  James l. Gallagher, Inc. proposes to address this issue by combining a commercially proven through-thickness 3-D reinforcement technology with a robotic controlled automated insertion head.  In the Phase I Feasibility study for this proposal, test data showed that select 3-D reinforcement significantly improves the interlaminar strength of 2-D C/SiC.  Preliminary manufacturing studies suggest that a specially designed 3-D reinforcement head can be readily adapted to one of several commercially available robotic end effectors.  Initial rate estimates indicate that such a design would provide cost effective 3-D reinforcement in part sizes and part geometries of interest to the hypersonic weapons community.