Review of preparation processes and joining performance of ceramic matrix composite fasteners

Thermal structural components made of continuous fibre-reinforced silicon carbide ceramic matrix composites (CMC-SiC) have been widely employed in aerospace and aeronautical fields. Integrated manufacturing techniques have been also extensively utilized to assembly CMC-SiC parts together to form large and complex components. The development of novel high-performance CMC-SiC fasteners has become critical manufacturing technology. In this work, different types, preparation methods, and microstructural characteristics of CMC-SiC fasteners were reviewed based on unique demands in terms of component preparation. It is demonstrated that shear strength of fasteners was very similar to in-plane shear strength of composites. Tensile and shear behaviours, load distribution among fasteners, failure mechanisms, and oxidation damages of CMC-SiC bolted/pinned joints were summarized. Furthermore, vibration relaxation mechanism and related anti-loosening effect were discussed. Accordingly, an optimization of CMC-SiC fasteners was proposed based on fibre architecture design, preparation process, and fastener structure. In the last, the development of CMC fastener manufacturing and their joining perfor-mance was prospected.