There are significant differences in erosion resistance between refractory bricks and clay bricks, which are mainly reflected in the following aspects:

I. Chemical composition and erosion resistance

Clay brick: The Al₂O₃ content of clay brick is usually between 30% and 48%, and it belongs to weakly acidic refractory material, which has certain corrosion resistance to acidic slag and gas, but has weak corrosion resistance to alkaline substances.

With the increase of Al₂O₃ content, its alkaline corrosion resistance will be enhanced.

Refractory bricks (especially high-alumina bricks): The Al₂O₃ content of high-alumina bricks usually exceeds 48%, and can even reach more than 75%. Its corrosion resistance is better than that of clay brick, and it can resist the corrosion of acidic and alkaline slag.

The higher the Al₂O₃ content in high-alumina brick, the more mullite and corundum components, and the less glass phase, the stronger the corrosion resistance.

II. Porosity and erosion resistance

Clay brick: The porosity of ordinary clay brick is relatively high, usually around 26%, which makes its corrosion resistance relatively weak.

Refractory bricks (such as low porosity clay bricks): Low porosity clay bricks have lower porosity, usually less than 17%, which makes them have higher density and better corrosion resistance.

Refractory bricks with low porosity can better resist the erosion of high temperature gas and molten substances.

III. Application environment and erosion resistance

Clay brick: it is suitable for industrial furnaces and kilns with weak acid environment and temperature not exceeding 1250℃, such as ferroalloy kilns and aluminum plants.

In the aggressive environment such as regenerator of glass kiln, the service life of ordinary clay brick is short.

Refractory bricks (especially low porosity clay bricks): Low porosity clay bricks are especially suitable for corrosive environments, such as regenerator of glass kiln, because of their excellent corrosion resistance.

High alumina brick is suitable for high temperature environment and parts that need to resist acid and alkali erosion.

IV. Influence of other factors on erosion resistance

Clay brick: the erosion resistance of clay brick is also affected by its production technology and raw material purity.

Refractory bricks: By adding flint clay and other raw materials, the porosity can be further reduced and the corrosion resistance can be improved.

The corrosion resistance of refractory bricks is also closely related to their thermal shock resistance, oxidation resistance and other properties.

V. Summary

Clay brick is relatively weak in erosion resistance and is suitable for industrial furnaces in weak acid environment and low temperature. Refractory bricks (especially high alumina bricks and low porosity clay bricks) have higher corrosion resistance and are suitable for high temperature and corrosive environment. When selecting refractory materials, the appropriate brick type should be selected according to the specific use environment and the nature of corrosive media.