Silicon Carbide Bricks

Silicon Carbide Bricks Description

Silicon carbide bricks are burned firebricks which adopts industrial SiC as main raw material. The binders used to make SiC brick include: aluminum silicate, nitride, etc. SiC based firebricks, which contain less than 50% of SiC, is called semi SiC bricks. Semi SiC refractory bricks include clinker SiC bricks, high alumina SiC bricks, zircon SiC bricks, mullite SiC bricks, corundum SiC bricks, etc. Silicon carbide bricks character in high cold and hot mechanical strength, low linear expansion rate, high thermal conductivity, good thermal shock resistance, excellent high temperature wear resistance and strong chemical corrosion resistance. The main applications of silicon carbide bricks are steel industry, nonferrous metals industry, chemical industry, power plants, ceramics industry and so on.

Clay Bonded Silicon Carbide Bricks

Clay bonded silicon carbide bricks belong to aluminum silicate bonded SiC bricks, SiC content is usually between 50%~90%. Clay is used as binders, and sillimanite, andalusite, kyanite fine powder are added into raw material to improve high temperature performance. The higher clay content, the better oxidization resistance, but the lower shock resistance and high temperature mechanical strength. Clay and aluminum silicate minerals contains some ratio of R2O, RO  and Fe2O3 impurities, which can affect hihg temperature performance of clay bonded SiC bricks, so high temperature performance of clay bonded silicon carbide bricks is not so good.
Clay bonded SiC refractory are mainly used as muffle boards of various kinds of industrial kilns and furnaces, ceramics kiln furniture ( refractory slab, sagger and so on). But clay bonded silicon carbide products has these disadvantages: high temperature performance is not good, the thickness and weight of kiln furniture is too high, production efficiency it low, energy consumption is high, so it is seldom used.

Mullite Bonded Silicon Carbide Bricks

Mullite bonded silicon carbide bricks have better high temperature performance than clay bonded SiC bricks. High purity Al2O3 and SiO2 micro powder or fine powder are used as binding phase material, sometimes sillimanite, andalusite and kyanite fine powders are also added. mullite bonded SiC bricks usually contain 65%~85% of SiC, its sintering temperature is about 1350~1500℃. Mullite bonded SiC bricks are widely used in ceramics industry, nonferrous metals industry, machinery industry and so on.

Silica Bonded Silicon Carbide Bricks

SiO2 bonded SiC bricks adopts high purity SiO2 micro powder as binding agent, small amount of MnO2, V2O5 and other mineralizer are also added into raw material. The sintering temperature of Silica bonded SiC brick is about 1350℃~1500℃. SiO2 bonded SiC bricks have higher high temperature modulus of rupture than mullite bonded SiC bricks, they are mainly used as kiln furniture.

Silicon Carbide Bricks  Physiochemical Index
 

 
Nitride Bonded Silicon Carbide Bricks

Nitride bonded silicon carbide bricks compromise: Si3N4 bonded SiC bricks, Sialon bonded SiC bricks, Si2N2O bonded SiC bricks and other single phase or composite phase nitride bonded SiC bricks.

The main applications of nitride bonded silicon carbide bricks are steelmaking industry, nonferrous metals metallurgy, ceramics industry, etc. For example, Si3N4 bonded SiC bricks are widely used in blast furnace shaft lower part and tuyere suit, aluminum cell inner lining and kiln furniture.