NSF Award
0091576
This Small Business Innovation Research (SBIR) Phase II project will build on results of Phase I research to fully demonstrate an early warning system for potential failure of ceramic matrix composite (CMC) materials. In Phase I, a novel detection technique called Composite Failure Onset Response Test (ComFORT (TM)) was demonstrated for use with high temperature CMCs. ComFORT (TM) is a composite failure detection technique whereby proprietary thermally stable electrically conductive ceramic fibers are selectively placed, together with regular reinforcing fibers, and are then processed into a dense ceramic composite. Once in place, existing hardware is used to monitor the condition and the health of the electrical signal, while an especially designed algorithm minimizes false negatives during use. As the ceramic composite begins to fail, the failure of the fiber reinforcement is preceded by the failure of the conductive coating, which is recognized through a weakening or loss of electrical conductivity. This novel technique lends itself to a powerful early warning system, whereby the conductive fiber can be designed to fail before catastrophic failure of the composite itself. Proper placement of these conductive fibers enables tracking of even minute levels of breach within the composite. Moreover, through a novel design, it may be possible to extend the performance to detect matrix cracking. The lack of reliability and little to no warning before catastrophic failure has prevented a more widespread use of CMC's. The smart fiber system to be developed in this project will allow the use of CMC's in more demanding applications with greater certainty of success.<br/><br/>The successful commercialization of the proposed technology will lead to the insertion of continuous fiber reinforced composites into power generation, energy, air, space and missile applications, where high temperature, lightweight, and mechanically reliable materials are needed, and the cost of part failures is high. Ceramic composites can be used in a larger number of these applications, if part reliability can be assured. Substantial benefits in operating efficiency of gas turbine, automotive and rocket systems can be realized with increased operating temperatures.
