MAGNESIA REFRACTORIES CONTAINING CALCIUM ZIRCONATE IN THE MATRIX

摘要

The microstructure and properties of magnesia refractories containing calcium zirconate in the matrix are presented. In experiments, magnesia clinker with a CaO/SiO2 mole ratio of above 2 and dolomite - zirconia clinkers with different contents of secondary oxides were used. The dolomite - zirconia clinkers were produced by sintering of natural dolomites and technical zirconia at the two-degree firing process. The dolomites differed between themselves with small amount of admixture oxides. Mineralogically, the refractory materials consisted of periclase and calcium zirconate and small amounts of silicate phases. Therefore, these materials were characterized by high refractory, high endurance strength, very good chemical corrosion resistance and better thermal shock resistance than magnesia materials. They would be the alternative materials in relation to the magnesia spinel refractories.