Chrome corundum brick

Chrome corundum brick

Various varieties of chromium corundum products with chromium oxide content from 10% to 70% are produced. This type of material is composed of Al2O3/Cr2O3 solid solution and α-Cr2O3 phase and a small amount of mullite and baddeleyite phases. Low-grade materials may contain some corundum phases. The Al2O3/Cr2O3 solid solution is a special crystal phase structure, and the dense material makes it more resistant to corrosion than the pure corundum phase, and greatly reduces the transformation of Cr3+ to Cr6+.

1. The corrosion resistance of chrome corundum brick

With the increase of Cr2O3 content, the corrosion resistance of this material is also gradually enhanced. The corrosion test test shows that this material can be equivalent to or even stronger than the fused material in corrosion resistance with the change of Cr2O3 content.

2. Thermal expansion and thermal shock resistance of chrome corundum brick

Another advantage of chromium corundum material is that the thermal expansion curve is linear while the thermal expansion curve of fused cast AZS is irregular. Due to the degree of elasticity of this structure, the internal thermal stress is greatly reduced. In addition, the presence of zirconia particles in the microstructure of this material also inhibits the generation of internal cracks. Therefore, the chrome corundum material has better thermal shock resistance compared with the isostatically pressed material, so it is well used in the high load area of the kiln and the most suitable hot repair material such as the patching brick of the liquid level line.

3. Application and development of chrome corundum brick

Based on the good corrosion resistance and thermal shock resistance of chrome corundum brick, the popularization and application of chrome corundum materials will effectively prolong the operating life of the pool furnace and generate long-term economic benefits.

Using chrome corundum brick as kiln pool wall tiles

Chrome corundum brick was used as a supplementary material for eroded pool wall bricks (including electrode bricks) in a horizontal flame bottle kiln. The bricks were in contact with the glass liquid immediately after installation, but no cracks appeared during the installation process. The kiln was shut down after 3 years of operation, and only the individual maximum erosion was only 50mm at the liquid level. Glass companies using chrome corundum for tiling have never found any effect of coloration on glass quality. In China, it has been applied in Shanghai and Wuhan since 2005, and the effect is very good, and there is no second pool wall subsidy.

Use chrome corundum material as the key part of the inner layer of the kiln

Refractory bricks based on chrome corundum oxide ceramic bonding have been used for many years in various parts of the inner layer of glass furnaces. The application range of this refractory material involves glass wool, mineral wool and soda-lime utensils in the very critical inner layer of glass furnaces, such as the corners of the feeding end and the liquid hole, as well as the inner layer of the whole furnace. Continued improvements to this material have made it even more superior. RHI Austria magnesium can produce various kinds of chromium corundum products with chromium oxide content from 10% to 70%.

Extend the life of the pool furnace, study the chrome corundum material with the corrosion resistance equivalent to the isostatic pressing product, and reduce the cost

The chrome corundum refractory has been used in practice for many years to show that its strong corrosion resistance and scour characteristics fully meet the design requirements. In soda lime glass furnaces, they protect the most critical furnace parts well, and also make the furnace life of the glass fiber furnace with strong corrosion resistance reach 4-5 years. RHI's research department is continuously improving the properties of chromium corundum materials. New products continue to develop and achieve the same erosion resistance as isostatically pressed products.