C/C-SiC Materials for High Abrasive Resistant Structures

Abstract

C/C-SiC materials, originally developed for thermal protection systems of reusable spacecraft, offer high mechanical strength even at very high temperatures. Additionally, these materials can withstand high heating rates as well as extreme local temperature gradients and hot spots. Compared to other CMC materials based on chemical vapour infiltration (CVI) or liquid polymer infiltration (LPI), C/C-SiC materials based on the LSI process (Liquid Silicon Infiltration) offer economical advantages due to short process times and low cost raw materials. These unique properties make C/C-SiC materials promising candidates for thermally and mechanically extremely loaded jet vanes for thrust vector control systems in rocket motors. In this work, C/C-SiC materials based on different carbon fibre reinforcements (2D fabric, short fibres) and surface coatings (SiC, B4C) were investigated. The abrasive resistance was tested in a hot gas test bench based on a solid propellant, providing a high velocity and high temperature exhaust jet with a high amount of alumina particles. Thereby the influence of the material composition, especially the content of SiC, the fibre architecture and the surface coating on the abrasive resistance of characteristic specimen could be shown.