Ceramic-to-Metal Joining for High Temperature, High Pressure Heat Exchangers

Economical and efficient heat transfer technologies applicable to high-temperature, high-pressure conditions are a common requirement for advanced fossil energy power generation systems. High temperature and high pressure ceramic heat exchangers can improve cycle performance and improve durability. Ceramic components perform poorly in tension, requiring specialized engineering, in particular with respect to joining with adjacent components. In other words, joining ceramics to other high temperature metallic components is seen as an enabling technology for high-performance heat transfer components, and by extension high-efficiency power cycles. Personnel of Electron Technologies, Inc. (ETI) have developed new methods for joining ceramics to metals that give high strength, helium leak tight, high thermal transport joints for use at high service temperatures (>700 °C). Specifically, silicon carbide (SiC) will be joined to metal for use in both steam and supercritical CO2 power cycles. This will be an extension of the recently developed SiC joining technology for petrochemical plants, and will be the first application of this technology towards advanced fossil energy power generation systems. Design and test sintered silicon carbide to metal joining technology under high temperature and high pressure conditions. Determine if the joints maintain integrity and remain helium gas tight. These joined parts will be tested for mechanical strength, fracture toughness and hermeticity. A preliminary design for a complete heat exchanger with ceramic to metal joints with flanges will also be completed for testing in Phase II. This program will develop and test a green technology that will reduce carbon emissions and increase the efficiency of fossil fueled power plants. The silicon carbide to metal joining technology is expected to have many other industrial uses. Commercial Applications and Other Benefits: The main application is for industrial scale fossil fuel burning power plants. This technology will allow higher operating efficiency with a reduction in carbon emissions. Joining SiC-to-Metal has numerous applications anywhere there is a need for structures built to operate at very high temperature such as ethylene pyrolysis furnaces and solar concentrators.