Joining Silicon Carbide Components for Space Propulsion

This SBIR Phase I program will identify the joining materials and demonstrate the processes that are suited for construction of advanced ceramic matrix composite (CMC) thrusters for advanced monopropellants and bipropellants for space propulsion. We will join CMCs to each other and to superalloys by brazing. In Phase I, we will experimentally evaluate and identify suitable active metal braze alloys through wetting experiments, brazing, microstructural examination, and shear strength measurements both at room temperature and 1100ºC. We will also demonstrate the feasibility of using stiff and compliant interlayers to increase the joint strength by reducing the thermal residual stresses in the joints. The Phase II project will demonstrate a working CMC HAN thruster using the joining technology developed in Phase I.