materials

Silicon Nitride

Known for its exceptional hardness and both wear and thermal shock resistance, Silicon Nitride is an advanced technical ceramic used in extreme environments.

9.0

Relative Cost of Material

8.5

Machining Degree of Difficulty

Summary

Silicon Nitride is an extremely hard and wear resistant material- so much so that it was originally used in high-end cutting tools and abrasives for the manufacturing of other materials. In addition to its mechanical properties, it also is an excellent insulator with high thermal shock resistance, making it a favored material in many aerospace applications. Its relatively high material cost and degree of difficulty in terms of machining mean that many Silicon Nitride components are price-driven to be less geometrically complex, but complex parts such as turbines and rocket nozzles are still made on a frequent basis from this material. As a leading manufacturer of technical ceramic components, Click here to request a quote, and we will show you why more engineers are trusting us with their mission-critical needs.

Applications

Silicon Nitride is used in a variety of industries, ranging from manufacturing, to automotive, to aerospace, and also medical. As an extremely durable material (both in terms of its mechanical and thermal properties), Silicon Nitride is used in many high-temperature applications, such as rocket propulsion, as well as in automotive combustion chambers, as an electronic insulator, and in orthopedic medical applications.

Properties

Material PropertySilicon Nitride
Density (g/cm^3)3.2 - 3.31
Hardness (Knoop)1500 - 2100
Tensile Strength (MPa)586
Modulus of Elasticity (GPa)324
Flexural Strength (MPa)448 - 910
Compressive Strength (MPa)2999 - 3447
Poisson's Ratio0.27
Dielectric Strength (ac-kV/mm)17.7
Dielectric Constant (@1MHz)8.4
Volume Resistivity (ohm-cm @25°C)>1.0E13
Coefficient of Thermal Expansion (1 x 10^-6/°C)3.0 - 3.9
Thermal Conductivity (W/m K)15 - 30
Specific Heat (J/kg*K)544
Maximum Working Temperature (°C)1250
Shock Resistance (°C Differential)750
*Note: Properties vary by manufacturer. The above information should be used for general reference purposes only.

related Materials

  • Silicon Carbide – An extremely hard, extremely corrosion-resistant technical ceramic
  • Alumina – A high-purity ceramic with good mechanical, insulatory, and thermal properties
  • Aluminum Nitride – Softer ceramic with good thermal insulation and electrical resistivity

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