Improved Silicon Carbide Materials for Very High-Temperature, Fast-Spectrum Nuclear Energy Systems

72556B03-I Advanced materials are sought that can meet the very demanding conditions required for a fast spectrum nuclear energy system to operate at temperatures greater than 900¿C. Silicon carbide (SiC)-based materials are prime candidates and have received extensive investigation; however, there remains a need for improved material performance, reduced manufacturing costs, and improved fabrication techniques. This project will develop improved SiC materials and processing, using an innovative reaction-forming approach. This approach offers the potential for a highly refined SiC microstructure (less than 0.5 microns), no residual silicon phase, very high purity (greater than 99.99%), and numerous low cost processing and fabrication advantages, including the ability to be bonded. Phase I will fabricate samples of high density SiC, characterize microstructure and properties, and determine basic processing parameters. Toughened SiC ceramic matrix composite systems will be investigated, and bonding/joining techniques will be evaluated. Commercial Applications and Other Benefits as described by awardee: The development of SiC ceramics and composites, with significant performance improvements and low cost processing advantages, should be applicable as structural components for very high-temperature, fast-spectrum nuclear energy systems. Additional commercial applications include advanced turbine engine components, heat exchangers, automotive engine components, armor, cutting tools, and refractories.