Five advantages of high alumina brick

Compared with refractory clay bricks, the outstanding advantages of high alumina brick are high refractoriness and load-softening temperature. As the Al₂O₃ content increases, the slag resistance performance is significantly improved. Specifically, high alumina bricks have the following properties.

High refractoriness

The refractoriness of high-alumina brick is higher than that of clay brick and semi-silica bricks, reaching 1750~1790℃, which is a high-grade refractory material. The refractoriness is mainly affected by the content, type, and quantity of Al2O3. The refractoriness increases with the increase of Al2O3 content.

load softening temperature

Because high-aluminum products contain high levels of Al2O3, low impurities, and less fusible glass, the load softening temperature is higher than that of clay bricks. However, because the mullite crystals do not form a network structure, the load-softening temperature is still not as high as that of silica bricks.

Thermal conductivity

High alumina bricks have better thermal conductivity than clay bricks. The reason is that there is less glass with low thermal conductivity in high-aluminum products, and the number of mullite and corundum crystals with better thermal conductivity increases, which improves the thermal conductivity of the product.

Thermal shock stability

The thermal shock resistance of high alumina bricks is between clay products and siliceous products. The 850℃ water cooling cycle is only 3 to 5 times. This is mainly due to the fact that the thermal expansion of corundum is higher than that of mullite and there is no crystalline transformation. At present, the thermal shock stability of products can be improved by improving the particle structure of the product, reducing the content of fine powder, and increasing the critical particle size and particle gradation of clinker.

Slag resistance

High alumina bricks contain more Al2O3, which is close to neutral refractory materials and can resist the erosion of acidic slag and alkaline slag. Because it contains SiO2, its ability to resist alkaline slag is weaker than that of acidic slag. In addition, the slag resistance of high-aluminum products is also related to the stability of the products in the slag. Generally speaking, products with lower porosity have higher slag resistance after high-pressure molding and high-temperature firing.