Low-temperature fabrication and characterization of porous SiC ceramics

Porous SiC were prepared using SiC powders and polycarbosilane (PCS) as binder. During pyrolysis, PCS experienced an organic-inorganic transformation and bonded SiC powders at a low temperature of 1273 K. The flexural strength of porous SiC ceramics increased with increasing PCS content and shaping pressure, while decreased with increasing the carbon content. With the increasing of the content of carbon, the open porosity of SiC ceramics increased from 53.05% to 58.60%, while the flexural strength decreased from 7.88 MPa to 1.08 MPa. The average pore size of porous SiC ceramics decreased with increasing shaping pressure and decreasing particle size of SiC powders.