Thick-Section PIP Derived CMC Components

This work will focus on evaluating lower cost PIP processing of C-SiC composites for thick-section and large volume components such as blisk turbomachinery, nozzles, ramps, thrust chambers, ducting and other hot structures. A significant barrier to using composites in these applications involves processing limitations with respect to part size and volume. Processing routes utilizing chemical vapor deposition/infiltration (CVD/CVI) require high-temperature pressure reactors and rely on time/temperature dependent diffusion. As a result, CVD/CVI facility reactor dimensions limits the maximum part size while process physics limit the practical thickness/volume of parts to be infiltrated. Polymer infiltration and pyrolysis (PIP) processing may overcome such limitations. Although significant development has been done in the PIP processing of SiC/SiC systems, little work has been done with PIP C/SiC CMCs. Insufficient data and material properties exist for PIP processed thick cross section parts, which has hindered acceptance and application of this process. The work proposed here provides a baseline mechanical property database for PIP processed C-SiC CMCs, and provides the initial evaluation of thick section composites processed using the PIP approach and incorporating the latest advancements in process cost and schedule reductions.