Processing and properties of SiC and SiC/SiC composite materials by melt infiltration process

This paper dealt with the microstructures and the mechanical properties of monolithic SiC and SiC/SiC composite materials fabricated by the melt infiltration process. The characterization of melt infiltrated SiC and SiC/SiC composite materials with different sizes of starting SiC particles was investigated by means of electron microscopies, three point bending tests and single-fiber push-out tests. Based on the mechanical property-microstructure correlation, process optimization methodology also was discussed. The flexural strength of melt infiltrated SiC material strongly depended on the content of residual silicon, which associated with the preparation route of C/SiC matrix slurry such as the composition ratio of C and SiC particles and the size of raw SiC particles. MI-SiC/SiC composites represented good flexural strength, even if the instability of matrix morphology and the interfacial debonding were occurred.