Effect of Additive Composition in the Al2O3–MgO–MnO System and Firing Temperature on Sintering of Composite Ceramic Based on Electromelted Corundum

Abstract

The effect of eutectic composition additive content in the Al₂O₃–MgO–MnO system on sintering of structural ceramic based on electrocorundum is studied. The starting material used is electrocorundum grade F-1000 with an average particle size of 10 μm. Additive powder is prepared by thermolysis of manganese carbonate, magnesium carbonate and aluminum hydroxyl salts. Spinel MgO·Al₂O₃ and MnO·Al₂O₃ are synthesized separately. It is established that with a content of 15 wt.% additive after firing at 1550°C ceramic density reaches 3.86 g/cm³ with 0.3% open porosity, and the ultimate strength in bending comprises 211 MPa.