Properties of Porous Mullite Ceramics Doped with MgO and Produced by Slip Casting Method

Proceedings of VII International Scientific Conference „Refractories, Furnaces and Thermal Insulations 2012” 2012
Ludmila Mahņicka-Goremikina, Ruta Švinka, Visvaldis Švinka

Porous mullite, mullite-corundum ceramics with highly open porosity were prepared by slip casting method using Al paste as the pore former. In the present investigation, the samples were obtained from to types of alumina oxides powders (α-Al2O3 and γ-Al2O3), SiO2 and kaolin, some compositions of samples were doped with MgO additive. Al2O3 and SiO2 in all samples were in 2.57:1 ratio, because that was conformed by mullite stechiometric compositions (3Al2O3.2SiO2). The ratio of α- and γ-Al2O3 was 1:3. 30 wt% of kaolin was as additional component in the mix of Al2O3 and SiO2. The quantity of MgO was 5 wt%. Ceramics were sintered at the temperatures of 1200, 1300 and 1750oC. The influence of starting raw materials and MgO additive has been studied by main testing as differential thermal analysis, XRD diffraction, Hg porosimetry, nondestructive acoustic method and three point bending strength.

Keywords
kaolin, alumina, silica, porosity, MgO, magnesia, mullite, mullite-corundum

Mahņicka-Goremikina, L., Švinka, R., Švinka, V. Properties of Porous Mullite Ceramics Doped with MgO and Produced by Slip Casting Method. In: Proceedings of VII International Scientific Conference „Refractories, Furnaces and Thermal Insulations 2012”, Slovakia, Novi Smokovec, 17-19 April, 2012. Novi Smokovec: LUMA CAF, 2012, pp.130-135. ISBN 978-80-553-0889-9.

Publication language
English (en)