Production and permeability of porous Si3N4 ceramics produced by starch addition

• We produce highly porous (up to 66%) Si3N4.
• We enhance the permeability of Si3N4 by using starch as pore former.
• Increasing starch amount (≥20 vol.%) created large and bimodal pore channels and permeability values of these samples are quite higher.
• Pore size is more predominant than porosity on permeability.

In this study, the possibility of enhancing permeability of porous Si3N4 ceramics was studied by using pore former additive (potato starch; 0–30 vol.%). The open porosity of samples changed between 52 and 66% as the mean pore channel size values ranged from 0.9 to 4 μm. Increasing starch addition provides bimodal distribution of pore size channels by accompanying abrupt increment in non-Darcian permeability. k2 value rised from 8.7 × 10−10 m to 30.1 × 10−10 m.