Novel Materials for Metal to Ceramic Transitions

High temperature heat exchangers are seen as an enabling technology for advanced fossil energy power generation systems, such as systems that utilize power cycles based on steam or supercritical CO2. Effective ceramic to metal joining is seen as a key technology gap for high-temperature heat exchangers that, if overcome, may enable designers to exploit the high temperature corrosion resistance of many ceramic materials while utilizing a metallic structure to provide the required resistance to tensile forces caused by pressure fluctuations HiFunda and Boise State University (BSU) will work together to develop a new method to join highly thermally stable, high thermal conductivity ceramics such as silicon carbide (SiC) with candidate high- temperature structural alloys with the transition having sufficient strength and toughness to accommodate pressure cycles. In this project, HiFunda and BSU will identify and evaluate candidate transition materials, fabricate ceramic-metal joints with these materials and down-select specific compositions that can withstand pressure cycles up to 1500 psi and temperatures of 700oC. HiFunda will develop a novel joining technology with the potential to enable integration of key technologies such as supercritical CO2 cycles that can significantly increase efficiencies and reduce power system size. The technology platform developed will find application across a broad range of industrial sectors resulting in improved energy efficiency and cleaner technology. Commercial Applications and Other Benefits: Highly efficient heat exchangers, especially based on supercritical CO2, represents a key enabling technology for increasing efficiency and lowering cost in various applications involving advanced fossil power generation systems, as well as concentrated solar power and next generation nuclear plants. In addition to the target application of this proposal, namely heat exchanges for power systems, ceramic to metal joining is also needed for a variety of other types of equipment ranging from chemical reactors to microelectronics.