Effect of MgO/CuO on the Microstructure and Thermal Properties of Cordierite-Alumina Ceramics

摘要

Cordierite-alumina ceramics were prepared with the raw materials of cordierite and a-alumina powder, and TiO_2, CuO and MgO were added as composite additives. The effect of MgO/ CuO ratios on the microstructure, thermal conductivity and thermal shock resistance of cordierite-alumina ceramics were researched by X-ray diffraction, scanning electron microscopy and laser flash analyzer;;the bulk density and the porosity of cordierite - alumina ceramics were measured. The results show that with increasing of MgO/CuO ratios, the bulk density and thermal conductivity increase firstly and then decrease, and have a minimum with 0.4wt% MgO and 0.667 MgO/CuO;;and the porosity of ceramics decreases firstly and then increases and has a maximum with 0.4wt% MgO and 0.667 MgO/CuO;There are little changes in the size of the grain of the ceramics, and a small amount of magnesium aluminate spinel precipitate; the thermal shock resistance performance of the ceramics is developed with the increasing of MgO/CuO ratios.