Design, Manufacture, and Characterization of a Carbon Fiber-Reinforced Silicon Carbide Nozzle Extension

Nozzle extensions made of ceramic matrix composites (CMCs) have shown the potential to replace heavy superalloy nozzles and improve the performance of future upper-stage and orbital rocket engines. Gas permeability has been reported to be a critical issue during the manufacture for CMC nozzles. This work shows the manufacture of a dense radiation-cooled C/C-SiC nozzle demonstrator. A multi-angle fiber architecture was applied using filament winding technique to reduce the incidence of delaminations during the manufacturing process under high temperatures. Additional efforts were made to improve the final gas tightness and reduce the amount of residual silicon by means of an adapted liquid silicon infiltration process. The manufacture, the material, and structural characterization as well as a finite element analysis of a performed internal pressure test are presented.