Silicon Carbide Ceramics

silicon carbide (SiC ceramics not only have excellent room temperature mechanical properties, such as high bending strength, excellent oxidation resistance, good corrosion resistance, high wear resistance and low friction coefficient, but also high temperature mechanical properties (strength, creep resistance Etc.) is the best known ceramic material.

  • Description
  • Specifications
  • Silicon Carbide Ceramics

    silicon carbide (SiC) ceramics not only have excellent room temperature mechanical properties, such as high bending strength, excellent oxidation resistance, good corrosion resistance, high wear resistance and low friction coefficient, but also high temperature mechanical properties (strength, creep resistance Etc.) is the best known ceramic material. Hot press sintering, pressureless sintering, hot isostatic pressing of the material, its high temperature strength can be maintained at all times to 1600 °C, is the best high temperature strength ceramic materials. Oxidation resistance is also the best among all non-oxide ceramics.

    Because of its stable chemical properties, high thermal conductivity, low coefficient of thermal expansion, and good wear resistance, silicon carbide has many other uses besides abrasives. For example, silicon carbide powder is coated on a turbine wheel or cylinder block with a special process. The inner wall can increase its wear resistance and prolong its service life by 1 to 2 times. It is used to make high-grade refractory materials that are shock-resistant, small in size, light in weight, and high in strength and energy-saving. Low-grade silicon carbide (containing about 85% of SiC) is an excellent deoxidizer, which can accelerate the speed of steel making and facilitate the control of chemical composition and improve the quality of steel. In addition, silicon carbide is also widely used in the production of electric heating element silicon carbon rods.

    Silicon carbide has a very high hardness of 9.5 on the Mohs hardness scale, second only to the world's hardest diamond (Grade 10). It has excellent thermal conductivity and is a semiconductor that can resist oxidation at high temperatures.

    Due to its specific gravity of 3.2g/cm3 and high sublimation temperature (about 2700 °C) , silicon carbide is very suitable as a raw material for bearings or high-temperature furnaces. It will not melt at any pressure that can be reached, and it has a relatively low chemical activity. Because of its high thermal conductivity, high collapse electric field strength and high maximum current density, many people have tried to replace silicon with high-power semiconductor components. In addition, it has a strong coupling with microwave radiation and all its high sublimation points make it practical for heating metals.

    Material's mechanical properties:

     

    Silicon Carbide Ceramics Properties

    Color

    Black or Gray

    Density

    3.2g/cm3

    Melt Point

    1900

    Bending Strength

    500MPa

    Thermal Conductivity

    120 W/m.K

    Thermal expansion coefficient

    3.0×10-6 K-1

    Moore heat capacity

    28J/(MolK)

    Volume resistivity

    103ΩNaN

    Dielectric constant

    9.7@1Hz

     Hardness(Mohs)

    9.5