Joining of Nuclear-Grade SiC-SiC Composites by Localized Spark-Plasma Sintering

Rapid3Dmaterials, LLC will develop a new method of joining of ceramic materials based on the zone-selective spark-plasma sintering (SPS) technique- The project will be focused on the joining of SiC-SiC composites utilizing the localized generation of the Joule heat assisted by the passing electric current at- and in the vicinity of the joined components interface- This unique approach will provide an efficient energy distribution during SPS-Joining, enabling the cost reduction of the manufacturing process and the improvement of the properties of the joining interface- The proposed method does not assume the usage of any chemically different filler materials, thereby removing their possible detrimental impact on the mechanical and physical- chemical properties of the joined assembly- At the proposed Phase I of this project, the SPS-Joining process will be carried out in a spark- plasma sintering device utilizing a special design of the SPS tooling- By using the electrically conductive and electrically isolative tooling components, the SPS-Joining setup will enable a localized passage of the electrical current with the concentration of the electric current density in the areas of the immediate proximity of the joining interface- The joining process will be conducted using (i) direct joining of the polished SiC-SiC composite component surfaces, and (ii) using an additional layer of a SiC nano-powder deposited between the joined surfaces- The joining process will be conducted for tube-tube, tube-disk, disk-disk shaped pairs of components- The mechanical properties and the microstructure of the joining interfaces will be thoroughly characterized after SPS-Joining-