JIAO Chunrong 1, ZHAO Chunling 2, SUN Shijie 1, GAO Ye 1, YANG Jinhua 1,JIANG Kanghe 2, HE Yihong 2, JIAO Jian 1
(1. National Key Laboratory of Advanced Composites, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China; 2. AECC Hunan Aviation Powerplant Research Institute, Zhuzhou 412002, Hunan, China)
Abstract: SiCf/SiC composites are the landmark materials for new type of aeroengine hot-section component. The engine service environment of the turbine guide vanes is the most critical, while thermal shock resistance is one of the most important properties. In this paper, thermal shock resistance of blade body structures with different laminates of SiCf/SiC composites was studied. The effect of the laminate structure on the formation of defects in the blades and the water quenching thermal shock performance were evaluated. It is found that the blade with unidirectional laminated structure has uniform and dense microstructure, but its thermal shock resistance is the worst, which cracks completely after only ten cycles. Although there are more holes and defects in the blade with orthogonal lamination, it possesses stronger thermal shock resistance with more than 30 cycles. The ratio of the circumferential fibers should be more than 1/2, in order to achieve sufficiently high thermal shock resistance for the blade.
Key words: blade body; thermal shock resistance; water quenching