The objective of the proposed program is to demonstrate affordable high temperature joining technology applicable to both CMC to CMC and CMC to superalloy joints were demonstrated during the phase I SBIR effort using active metal brazes and preceramic polymers. While in many cases joining was successful, the temperature capability of the fabricated joints was limited to 600 degrees C. On the basis of these results, an approximately four-man-year, six task work plan has been assembled in this Phase II proposal to demonstrate the dual use potential for high temperature joining of the CMCs to CMCs and CMCs to superalloys. These include: the selection of superalloys compatible to CMCs for joining and modeling of CMC to superalloy joints (Task E.1); the evaluation of joining concepts based on active metal brazes, filled preceramic polymer, transient liquid phases, preform joining, and sintering of nanophase ceramic powders (Task E.2); structural and thermal characterization of downselected joining concepts (Task E.3); process scaleup and design of full scale joints (Task E.4); structural and thermal characterization of the full joined subcomponents (Task E.5); and reporting (Task E.6). Lanxide is fully committed to this 24 month program as demonstrated by the participation of Du Pont Lanxide Composites (commercial CMC manufacturer and Textron Lycoming (gas turbine engine manufacturer)as subcontractors. Lanxide is well equipped to carry out the planned work using existing personnel and facilities, which includes on-site R&D and production capabilities.
