Production Conditions of Nanoporous Ceramics Based on Mullite

Abstract

A technology for producing nanoporous ceramics based on mullite (3Al2O3 ⋅ 2SiO2) is developed. The mechanochemical activation of oxides involved in the synthesis of mullite (γ-Al2O3 and amorphous SiO2) makes it possible to obtain single-phase 3Al2O3 ⋅ 2SiO2 and to reduce its sintering temperature to 1300°С. The effect of the pressing pressure and the amount of pore-forming additive (ammonium carbonate) on the value of open porosity, pore volume, and pore size distribution in sintered ceramics 3Al2O3 ⋅ 2SiO2 is established. Mullite nanoceramics with open porosity of 42–47%, pore size <200 nm, and compressive strength 50–65 MPa is obtained.