Abstract:
The novel diatomite-based porous substrates were prepared via the combined processes including stirring mixing, isostatic pressing and sintering with the diatomite as the source material, carbon powder as the pore-forming material, and PTFE as the binder. The effects of pore-forming agent content, molding pressure and sintering temperature on the microstructure, phase composition, open porosity and bending strength of the substrates were investigated by the scanning electron microscope, X-ray diffractometer, Archimedes method and Three-point bending strength tests. The results indicated that the diatomite-based porous substrates with open porosity of 50.1%, apparent density of 0.97 g·cm
-3, bending strength of 4.43 MPa and relatively uniform pore size of 20 μm were obtained at the optimal preparation conditions of carbon content of 40%, forming pressure of 160 MPa and the sintering temperature of 1 000℃. The results expand the new application field for the development and utilization of mineral materials.