Silicon Nitride Ceramics

Silicon nitride is an advanced ceramic material with high hardness, stable structure, small thermal expansion coefficient, excellent resistance to oxidation and erosion, and excellent thermal and chemical properties.

  • Description
  • Specifications
  •  Silicon Nitride Ceramics

    Silicon nitride is an advanced ceramic material with high hardness, stable structure, small thermal expansion coefficient, excellent resistance to oxidation and erosion, and excellent thermal and chemical properties.

    Silicon nitride ceramics are inorganic material ceramics that do not shrink when sintered. Silicon nitride has high strength, especially hot-pressed silicon nitride, and it is one of the hardest substances in the world.

    The decomposition temperature of silicon nitride is 1800° C. in air and 1850° C. in 110 MPa nitrogen. Si3N4 has a low thermal expansion coefficient and high thermal conductivity, so it has excellent thermal shock resistance. The hot-pressed silicon nitride will not break when it is heated to 1000°C and put into cold water. At not too high temperatures, Si3N4 has high strength and impact resistance, but at 1200°C or more, it will break down with the increase of service time, lower its strength, and cause fatigue damage more easily above 1450°C, so Si3N4 The use of the temperature is generally not more than 1300 °C. Since Si3N4 has a low theoretical density and is much lighter than steel and engineering superalloy steels, it is appropriate to use Si3N4 ceramic instead of alloy steel in places where high strength, low density, and high temperature resistance are required. Now.

    Si3N4 ceramics is an important structural material. It is a kind of super-hard material. It has lubricity and wear resistance. It does not react with other inorganic acids except hydrofluoric acid, and it has strong anti-corrosion ability and high temperature resistance. Oxidation. And it can also resist the thermal shock, heated in the air to more than 1,000 °C, rapid cooling and then sharp heating, it will not break. It is because of such excellent characteristics of Si3N4 ceramics, people often use it to make bearings Mechanical components such as gas turbine blades, mechanical seal rings, and permanent molds. If a silicon nitride ceramic that is resistant to high temperatures and does not easily transfer heat is used to produce the heating surface of the engine components, it can not only improve the quality of the diesel engine, save fuel, but also increase the thermal efficiency.the electronics industry.

     

    Material's mechanical properties:

     

    Silicon Nitride Ceramics Properties

    Color

    Gray

    Density

    3.2g/cm3

    Melt Point

    1900

    Bending Strength

    1000MPa

    Thermal Conductivity

    25 W/m.K

    Thermal expansion coefficient

    2.7×10-6 K-1

    Specific heat

    800J/(Kg.)

    Volume resistivity

    1014ΩNaN

    Dielectric constant

    8.3@1Hz

     Hardness(Mohs)

    9