Membrane Porous Materials from Sialon

Carbothermal reduction and simultaneous nitriding of kaolin in pressings from a mixture with graphite are used to fabricate a ceramics based on β-sialon with a porosity of 50 – 60%, a pore size of about 1 μm, and a gas permeability of about 0.04 μm². Mercury porosimetry of one of the specimens shows a narrow size distribution of the pores with a maximum at 0.7 μm. The method used for fabricating the porous sialon is classified as reaction sintering, and the elevated permeability of the obtained sialon materials is associated with the negative volume effect of the reaction of carbonitriding of kaolin.