Advanced Materials and Processing Methods for CMC Ducts

Continuous fiber-reinforced ceramic composites (CFCCs) are inherently wear and oxidation resistant, retain strength at higher temperatures and have lower specific densities than competing metal systems. The hot sections of gas turbine engines and relateddevices are exposed to aggressive gaseous species at high temperature. Because of their thermochemical stability and oxidation resistance, continuous fiber-reinforced ceramic composites have been identified as leading material candidates for hightemperature applications; however, new processing methods are needed to lower the cost of producing these materials, and to produce them in forms that can be attached readily to supporting metal structures. Thor Technologies, Inc. will team with LosAlamos National Laboratory (LANL), Materials Research & Design (MR&D), and Allison Advanced Development Company (AADC) to integrate two novel technologies into an innovative, low cost method of producing hybrid CFCCs for turbine engine applications, suchas inter-turbine ducts. The novel polymer infiltration/microwave pyrolysis (PIMP) process enables the production of hybrid CFCCs, in which new features enable the use of conventional attachments (i.e., bolts). The PI has over fifteen years experience inprocessing CFCCs, and the team has the design, manufacturing, and testing expertise to produce inter-turbine engine ducts at low cost.The reduction in cooling air requirements will lower the overall weight and increase the operating efficiency of turbineengines ranging from aerospace engines to stationary power plants. The availability of low cost CFCCs will enable new industrial applications, such as corrosion-proof piping for chemical processing.