Silicon nitride bonded silicon carbide (Si3N4-SiC) bricks, also known as SiNSiC bricks, are a type of refractory brick that combine the properties of silicon nitride and silicon carbide. These bricks are commonly used in high-temperature applications where excellent thermal shock resistance and high strength are required. Here's what you need to know about silicon nitride bonded SiC bricks:
Composition: Silicon nitride bonded SiC bricks are composed of silicon carbide grains and a bonding phase of silicon nitride. The silicon carbide provides high-temperature strength, while the silicon nitride acts as a bonding agent, enhancing the mechanical properties and thermal shock resistance.
High-temperature resistance: SiNSiC bricks exhibit excellent high-temperature resistance. They can withstand temperatures up to 1450°C (2642°F) and maintain their mechanical strength and structural integrity at elevated temperatures.
Thermal shock resistance: SiNSiC bricks have exceptional thermal shock resistance. They can withstand rapid temperature changes without cracking or spalling, making them suitable for applications where thermal cycling occurs.
High mechanical strength: SiNSiC bricks possess high mechanical strength, allowing them to withstand the mechanical stress and load encountered in high-temperature environments. They exhibit good resistance to deformation and can support heavy loads.
Oxidation resistance: SiNSiC bricks have good oxidation resistance. The silicon nitride bonding phase acts as a protective barrier, preventing the penetration of oxygen and other oxidizing agents. This property helps to extend the service life of the bricks in oxidizing environments.
Corrosion resistance: SiNSiC bricks are resistant to many corrosive substances, including acids, alkalis, and molten metals. They can withstand chemical attack in various industrial environments, making them suitable for applications where corrosive conditions are present.
Low thermal expansion: SiNSiC bricks have a low coefficient of thermal expansion, meaning they do not significantly expand or contract with changes in temperature. This property helps to reduce the risk of thermal stress and cracking.
Application versatility: SiNSiC bricks find applications in a wide range of industries, including metallurgy, ceramics, chemical processing, and power generation. They are used in furnaces, kilns, incinerators, and other high-temperature equipment that require excellent thermal shock resistance and mechanical strength.
SiNSiC bricks are valued for their unique combination of properties, including high-temperature resistance, thermal shock resistance, high mechanical strength, and corrosion resistance. They are widely used in demanding industrial applications where reliable refractory materials are required to withstand extreme conditions.
 
Buy good quality low cost "Silicon Nitride Bonded SiC Bricks" having excellent thermal shock resistance, good alkali corrosion resistance, good slag resistance, high strength and high thermal conductivity, the bricks are mainly used in severe parts of iron-making blast furnace, such as the lower part of stack, belly, bosh and tuyere. 
 
Item
Unit
Data
SiC%
≥
 72
Si3N4 %
≥
21
Fe2O3 %
≤
0.5
Density
g/cm3
2.65-2.70
Apparent porosity %
≤
18
Modulus of Rupture
Mpa
(at ambient temperature)
42
Mpa(1400°C)
45
Compressive strength
MPA≥
150
thermal conductivity1250°C
W/m.k 
 15-18
acid-proof alkaline
 
Excellent
Size Difference
 0-100mm
±1.0
101-300mm
±1.5
301-500mm
±2.0
501mm above
±0.5%