Introduction to the performance of clay bricks

The properties of clay products fluctuate in a wide range, which is due to the large range of chemical composition of the products (the content of AI203 fluctuates between 30 and 46%) and the differences in production processes. The fire resistance of clay products fluctuates from 1580-1770 ° C. It mainly depends on the chemical composition of the products and increases with the increase of the ratio of Al203 / SiO2. The increase in flux impurities, especially alkali metal oxides, will significantly reduce the fire resistance of the product. The softening temperature of the load mainly depends on its chemical mineral composition and density, but the latter does not affect the end temperature of the softening of the load, but increases the starting deformation temperature. The lower bulk density of bricks will also lower the temperature at which the load begins to soften.

 

Therefore, to increase the load softening starting temperature of clay products, it is generally necessary to proceed from the following aspects: increase the Al2O3 content in the product, especially the Al2O3 content of the matrix; increase the firing temperature and the use of multiple clinker ingredients; improve the molding brick Bulk density.

Clay bricks have better thermal shock resistance and a large range of fluctuations,-generally more than 10 times (1100 "C water-cooled), which is not too large as the linear expansion coefficient value of clay products (average between 20 and 1300 ° C The coefficient of linear expansion is 4.5X10-6-5.8X 10-6 / * C) and there is no polycrystalline brick deformation phenomenon and it is related to the structure with obvious grain structure.

 

Clay products are weakly acidic refractory products, and their acidity increases with increasing SiO2 content. It has a certain resistance to acidic erosion, but has a poor resistance to alkaline erosion. Therefore, clay products are suitable for use as acid kiln refractories. Large clay refractory bricks for glass kiln are clay refractory bricks with a unit weight of not less than 50 kg for building glass kiln.