Preparation of Dispersed Zirconia Barium Aluminosilicate Composites

摘要

The potential for preparing a ZrO_2-containing ceramic composite based on barium feldspar (BaAl_2Si_2O_8) using the reaction sintering of zircon has been investigated. It is demonstrated that, through the reaction of ZrSiO_4, Al_2O_3 and BaCO_3 above 1400℃, a distribution of ZrO_2 particles in a BaO·Al_2O_3·2SiO_2 matrix can be achieved. A glassy phase rich in Si and Ba surrounds the zirconia par-tides and infiltrates the grain boundaries of the polycrystalline feldspar matrix. The tendency of the ZrO_2 particles to agglomerate within the matrix can be reduced by incorporating additional silica into the reaction, while limited stabilisation of tetragonal ZrO_2 can be achieved by additions of Y_2O_3 which partition between the ZrO_2 and the glassy boundary phase.