Microstructure and Properties of Melt-Infiltrated SiCf/SiC Ceramic Matrix Composite
HU Jianbao1, YANG Jinshan1, ZHANG Xiangyu1, DING Yusheng1, ZHOU Haijun1, GAO Le1, WANG Zhen1, HE Ping1, DONG Shaoming1,2
1. Structural Ceramics and Composites Engineering Research Center, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai 201800, China;
2. Shanghai Institute of Genomics, Shanghai 201800, China
SiCf/SiC ceramic matrix composite is the key material of thermal structural component of turbine. Highly dense KD-II SiC fiber reinforced SiCf/SiC composite was fabricated by melt infiltration of silicon. The microstructure, mechanical properties, thermal properties and oxidation resistance under 1200℃ or above were studied. The porosity of meltinfiltrated SiCf/SiC is only 1.6%. The flexural strength of SiCf/SiC composite at room temperature and 1200℃ are (521±89) and (576±22)MPa, respectively. SiCf/SiC composite shows non-brittle failure characteristic. The thermal conductivities of thickness direction at room temperature and 1300℃ are 41.7W/(m · K) and 18.9W/(m · K). The flexural strength of meltinfiltrated SiCf/SiC composite oxidized for 1000h at 1200℃ is (360±54)MPa, which is only decreased by 19%. The meltinfiltrated SiCf/SiC composite possess excellent oxidation stability, which is promised to be used as thermal structural material in turbine energy.