Sialon bonded SiC refractories are normally β-Sialon bonded SiC material. Sialon is the general name of compounds consisted of Si, Al, O, N and other elements. β-Sialon has many similar properties of Si3N4 based ceramic material, such as high rigidity, excellent mechanical performance, corrosion resistance, thermal shock resistance, low linear expansion coefficient. Its thermal conductivity is lower than β-Si3N4, but oxidization resistance is better than β-Si3N4, as well as better corrosion resistance to Al, Fe and Zn molten liquid and alkali.
Sialon bonded SiC bricks are mainly used as inner lining of blast furnace bosh or furnace belly. It is regarded as the second generation of SiC bricks used for blast furnaces. The principle crystalline phase of Sialon bonded SiC material is SiC, secondary phase is β-Sialon. Sialon bonded SiC bricks have relatively more Al2O3 compared with Si3N4 bonded SiC bricks.
For blast furnace SiC refractory, SiC content is usually between 70%~80%. With the SiC content, Sialon bonded SiC refractory has slightly higher linear expansion coefficient than Si3N4 bonded SiC refractory, while slightly lower thermal conductivity.
Sialon Bonded Sic Refractories Characteristics
Sialon bonded SiC refractory has very excellent high temperature and high temperature mechanical performances, most Sialon bonded SiC refractory’s 1400℃ modulus of rupture(MOR) is higher than cold MOR.
Sialon bonded SiC refractory also has excellent alkali corrosion resistance. Its alkali corrosion resistance is significantly better than Si3N4 bonded SiC refractory, which makes it more suitale to be used in places of blast furnace where have severe alkali corrosion.
Sialon bonded SiC has excellent oxidization resistance.
Sialon bonded SiC has excellent thermal shock resistance.
Sialon bonded SiC has excellent blast furance slag corrosion resistance.
Generally speaking, compared with Si3N4 bonded SiC material, Sialon bonded SiC has better basic slag corrosion resistance, iron, aluminum and other molten metal corrosion resistance.
Sialon Bonded Sic Refractory Application
Sialon bonded SiC products have been applied in many large scale blast furnaces, molten reduction iron smelting furances (COREX furnace lining, where has severe corrosion damage). Sialon bonded SiC are also used in nonferrous metals industry, such as zinc smelting, aluminum smelting and so on.
