Design, Fabrication and Testing of CMC Combustor Liner

In this chapter, the design, fabrication and testing of CMC combustor liner were investigated. The service performance analysis of the combustor liner was at first analyzed. The SiC/SiC combustor liner with the dimension of 296.48 mm (maximum diameter of outer liner) × 149.85 mm (minimum diameter of inner liner) × 100.46 mm (height), a wall thickness of 3–10 mm (including splicing structure) was fabricated using the CVI process. The surface of the SiC/SiC combustor liner was coated with EBC (Environmental Barrier Coatings, EBC) to improve the reliability and durability. Pulsed laser micromachining technology was used to realize the precise processing of SiC/SiC combustor liner micro-holes, and ultrasound-assisted machining technology was used to meet the demand for high-precision profile processing for various air-film holes with diameters larger than 0.5 mm, and the roughness can reach Ra = 0.3~0.5. After the inner and outer liners and other components have been densified and processed, the SiC rivets are used for on-line riveting, which achieves a connection result equivalent to “metal riveting” after CVI-SiC deposition, improves the ability of components to maintain the profile, and prevents delamination of combustor liner during the service life. On October 14, 2022, the ground ignition and performance test of the combustor liner was conducted. The average gas temperature was 1426 °C, with localized hot spots reaching 1734 °C. Localized EBC coating peeling was found after the ground testing.