China's Refractories

Abstract:

Dense corundum-mullite brick for blast furnace ceramic pad was prepared using white fused corundum and tabular corundum as aggregates, andalusite fine powder, sillimanite fine powder, zircon sand powder and Guangxi soil as the matrix, and phosphate as the binder, introducing different amounts of α-alumina micropowder, tabular corundum fine powder and fused corundum powder. The properties of the prepared brick were studied. The results show that, the brick with 10 mass% of tabular corundum fine powder fired at 1 560 ℃ for 3 h in a tunnel kiln has the bulk density of 3.08 g · cm ^-3, the apparent porosity of 13.2%, the cold compressive strength of 178 MPa, the molten iron corrosion rate of 0.6%, the slag corrosion rate of 6.4%, the alkali resistance strength decreasing rate of 7.5%, and the thermal shock resistance of 32 cycles, which is both dense and of good thermal shock resistance. The slag resistance simulation test was performed, which proved that the prepared corundum-mullite brick is better than those currently supplied in the market.

Key words: corundum-mullite brick, density, tabular corundum, fused corundum, α-alumina;