Investigations on Material and Mechanical Properties, Air‐Permeation Behavior and Filtration Performance of Mullite‐Bonded Porous S i C Ceramics

A theoretical relation between processing parameters and porosity (29–56%) of mullite‐bonded porous S i C ceramics was derived and validated with experimental data. Porosity‐dependent variation of fracture strength (9–34 MPa) and elastic modulus (7–28 GPa) was explained by the minimum solid area model. At room temperature, the D arcian, k 1 (1.2 × 10 −13 –1.6 × 10 −12 m 2 ) and the non‐ D arcian, k 2 (4.6 × 10 −9 –2.7 × 10 −7 m) permeability coefficients showed linear variation with porosity. Tests conducted up to 650°C indicated an increase in k 1 with temperature and a reverse trend for k 2 . Airborne N a C l nanoparticle filtration tests showed good performance of S i C ceramics with fractional collection efficiency of >99% at 46–56% porosity levels.