November 28, 2023
The corundum brick is a kind of refractory brick with alumina content greater than 85%, corundum brick is divided into sintered and fused corundum brick, and chrome corundum refractory brick is added to corundum Cr2O3, after high temperature molding, high temperature sintering of high-grade refractory brick, chrome corundum refractory brick is also divided into fused cast chromium, sintered chrome corundum refractory brick.
The differences between the two kind of bricks:
The refractoriness of chrome corundum brick is greater than 1790℃ and the load softening temperature is greater than 1700℃, the use temperature of corundum refractory brick is 1600℃, and the high temperature performance of chrome corundum refractory brick is better than that of pure corundum brick.
The compressive strength of corundum refractory brick is 70-100MPa, and the compressive strength of chrome corundum brick is greater than 150MPa at room temperature, which is significantly higher than that of corundum brick. Al2O3-Cr2O3 solid solution is formed between particles and particles, between particles and fine powder, and between fine powder and fine powder, and the solid solution will connect the particles and fine powder together to greatly improve the strength of refractory bricks.
The thermal shock stability of chrome corundum refractory brick decreases with the increase of Cr2O3 content, that is, the thermal shock stability of chrome corundum brick with low Cr2O3 content is better than that of brick with high Cr2O3 content. Under normal circumstances, the Cr2O3 content of chrome corundum brick is between 12% and 20%; In particular, the AKZ chrome-corundum brick produced by adding a small amount of phase change additive has better thermal shock stability.
Corundum refractory brick is seriously eroded by slag, the slag will all penetrate into the brick, and along the internal pores of the brick into the surface, the surface of the brick becomes brown; Chrome corundum brick is almost not corroded by slag, the boundary between the inner hole edge and the residue is clear, and the slag penetrates little into the brick. The chemical corrosion and permeability of chromium-corundum refractory brick against gasification slag are better than those of corundum refractory brick.
Chrome corundum brick is usually used in glass kiln lining, hot metal pretreatment device, waste incinerator, gasifier lining and so on. Corundum brick is used in petrochemical and fertilizer industry cracking, conversion furnace, metallurgical industry steelmaking furnace, blast furnace and other high temperature kiln lining. Both products have their own advantages, but chrome corundum brick is more resistant to high temperature and erosion than corundum refractory brick. Corundum refractory brick is cheaper than chrome corundum refractory brick, suitable temperature, in order to reduce production costs, choose corundum refractory brick used in the right location and the right temperature, is also a reasonable choice.
