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Porous permeable materials are prepared by selecting the grain size composition with electromelted corundum filler and porcelain mix PFL-1 binder. Specimens with an improved set of properties are prepared with addition to the composition of 5 wt.% porcelain binder (above 100% filler) after firing at 1450°C. Specimen ultimate strength in bending is 14.6 MPa, open porosity 44%, and gas permeability coefficient 0.85 μm2.

Porous permeable materials of electromelted corundum with fineness of 2 – 3 and 0.5 mm are prepared with a porcelain mix binder. Ratios in filler fractions 2 – 3 and 0.5 mm: 0/95, 35/60, 40/55, 45/50, 50/45, and 95/0. Specimens are compacted under a pressure of 24, 50, and 100 MPa and fired at 1350 and 1450°C. Sintered specimen ultimate strength in bending is from 1.9 to 15.3 MPa, open porosity 17 and 26%, gas permeability coefficient of single-fraction compositions from 1.19 to 3.27 μm2. The porous permeable ceramic material obtained is promising for use in the form of filters and ceramic membrane substrates.

Strong porous permeable ceramic is studied, prepared by selection of grain size compositions with filler of electromelted corundum grades F600 (100 – 200 μm), F360 (40 – 60 μm), and F120 (10 – 20 μm). The strengthening binders used are very fine corundum powder (~2 μm), alloyed with 0.25 wt.% MgO; a mixture of SiC (particle size 3 – 4 μm) and MgO (particle size 1 – 2 μm) in a ratio of 2:1. Specimens in the form of bars 60 × 15 × 5.5 mm are prepared by uniaxial semidry compaction under a pressure of 50 MPa (for single fraction compositions) and 25 MPa (for three-fraction compositions). Specimens are fired in air at temperatures from 1350 to 1550°C. Specimen open porosity varies from 28 to 43%, and ultimate strength in bending from 1 to 36 MPa. The best strength is obtained using a binder in the system SiC–MgO (5 wt.% binder above 100% of filler, σben = 36 MPa, and open porosity is 30%).

Porous permeable ceramic is prepared from electromelted corundum (EMC) with fineness of about 0.5 mm with added porcelain. Compositions are prepared with different ratios of EMC/porcelain: 99/1, 97/3, 95/5, 93/7, and 90/10. Specimens in the form of bars with a size of 40 × 7 × 6.5 mm are prepared by uniaxial semidry compaction under a pressure of 25 and 50 MPa and fired at 1350 and 1450°C. Specimen open porosity varies from 22 to 30%, and ultimate strength in bending from 1.1 to 9.3 MPa. Porous ceramic is promising for filters and ceramic membrane substrates.

A study is made of a strong porous ceramic based on granular mixes of a filler—electrofused corundum with particle sizes of 2 – 3 and 0.5 mm (95 wt.% of the mix) — and a porcelain binder (5 wt.%). Several mixes were prepared with different values for the 2 – 3 mm/0.5 mm ratio of filler-particle sizes: 0/95, 35/60, 40/55, 45/50, 50/45, and 95/0. The specimens were pressed at pressures of 25, 50 and 100 MPa and fired at temperatures of 1350 and 1450°C. The sintered specimens ranged from 19 to 143 MPa in ultimate flexural strength and 17 to 26% in open porosity. The results are attributed to the formation of a framework in the semifinished product along with regions outside the framework. The new porous permeable ceramic is promising for use in the form of filters and supports for ceramic membranes.