Factors that influence the flexural strength of SiC-based porous ceramics used for hot gas filter support

The influences of molding pressures, bonding phase contents, and SiC particle sizes on the flexural strength of SiC-based porous ceramics were investigated based on their microstructure of fracture surface. The SEM morphologies and EDS element analysis results of fracture surface showed that there were two different kinds of fracture points: SiC particle fracture points and bonding phase fracture points. It is found that molding pressures, bonding phase contents, and SiC particle sizes affect the SiC particle fracture point area in the fracture surface, and the fraction of the SiC particle fracture point area in the minimum solid area of fracture surface is a determined influence factor for the flexural strength of SiC-based porous ceramics used for hot gas filter support.