High-temperature CMC Processing for Ceramic-to-Ceramic Joining and for Interlaminar Strength Evaluation
Navy SBIR FY2008.2

Sol No.: Navy SBIR FY2008.2
Topic No.: N08-154
Topic Title: High-temperature CMC Processing for Ceramic-to-Ceramic Joining and for Interlaminar Strength Evaluation
Proposal No.: N082-154-0034
Firm: MATECH Advanced Materials
31304 Via Colinas, Suite 102
Westlake Village, California 91362-3901
Contact: HeeMann Yun
Phone: (818) 991-8500
Web Site: www.matechgsm.com
Abstract: There is a strong need to develop and demonstrate inter-laminar tension test methods for CMC at high temperatures in NAVY JSF Program for aero-engine components. MATECH GSM (MG) proposes to address this need by employing a variety of innovative low-cost pre-ceramic polymer-derived high temperature CMC adhesives between CMC test coupons and push rods. MG's high-temperature CMC adhesives are designed to facilitate ceramic-to-ceramic joining for the purpose of evaluating high temperature interlaminar strengths. Traditionally, joining adhesives are mainly developed for bonding two dissimilar materials; hence its structural performances, particularly off-axis behaviors accompanied by a necessity of non-brittle failure are mostly neglected. The CMC adhesives proposed here is a ceramic matrix composite that demonstrates graceful failure but is stronger than that of the test-coupons. Due to the two already existing given materials of the test-coupon and fixture, the newly added third material must be as physically close as possible to the other two materials from the beginning. The PIP CMC processing is only one densification method among several ceramic matrix formation routes that meet this first requirement. It is low-cost, a variety of active/non-active fillers can easily be added, and it is capable of forming shapes at low temperatures.
Benefits: Fabrication demonstration of CMC-based high-temperature adhesive joined CMC test-coupons onto the ceramic push-rod fixtures could benefit the NAVY JSF jet-engine propulsion development program for evaluating very thin-sectioned CMC component thru-thickness behaviors. This new high temperature CMC-adhesive approach for ceramic-to-ceramic joining is expected to offer significant benefits over existing traditional adhesives in off-axis handle-ability at elevated temperatures, thereby enabling more successful testing results and better interpretation of data at low costs. Potential commercial applications range from other industrial uses to energy production where high temperature CMC materials are attractive, such as high performance automobile brake-pads, high-temperature heat-treatment furnace heating-element and insulation materials, as well as future nuclear fusion reactors.