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Drawing No. EH–MT–021 // Engineering Materials

Silicon Carbide Ceramic Properties

Reviewed August 2026

Hexoloy SA is a dense sintered silicon-carbide ceramic with very high stiffness, hardness, thermal conductivity and corrosion resistance.

Saint-Gobain Hexoloy SA · sintered SiCSintered silicon carbideReference data — verify design allowables

Representative properties

The stated basis, temperature and direction are part of the value. Switch units without changing the physical reference.

Density
3,100 kg/m³
Reference value / stated test basis
Young’s modulus
410–430 GPa
Reference value / stated test basis
Poisson ratio
0.14
Reference value / stated test basis
Yield strength
N/A · brittle ceramic
Reference value / stated test basis
Tensile / comparison strength
380 MPa 4-point flexural · not tensile
Reference value / stated test basis
Thermal conductivity
126 W/(m·K)
Reference value / stated test basis
Specific heat
670 J/(kg·K)
Reference value / stated test basis
Thermal expansion
4.02 µm/(m·K), RT–700°C
Reference value / stated test basis
Melting / transition temperature
No simple ambient-pressure Tm · max service ≈1900°C
Reference value / stated test basis
Why this basis matters: SiC does not behave like a ductile metal and does not have a practical ambient-pressure metal-like melting point. Manufacturer service temperature and decomposition/sublimation behavior are more useful.

What changes these properties?

Engineering variability

  • Saint-Gobain publishes approximately 410 GPa on general Hexoloy SA material/application pages and 430 GPa on several finished-shape datasets; this reference therefore shows 410–430 GPa rather than a false single constant.
  • Strength is flaw-statistical and depends on surface finish and test method.
  • Thermal conductivity decreases substantially with temperature.
  • Different SiC processing routes—sintered, siliconized, nitride-bonded, recrystallized—have different properties.
  • Oxidizing/non-oxidizing atmosphere changes usable high-temperature limits.

Selection note

Excellent for seals, semiconductor equipment, heat-transfer parts, furnace fixtures, armor and chemically aggressive wear components.

Where a property is shown as qualitative rather than numeric, that is intentional: the selected source or the material physics does not justify a single comparable scalar.

How to interpret this material

Stiffness

Young’s modulus describes elastic stiffness. For crystals and composites, orientation can make one scalar modulus only a directional reference.

Strength / failure

Ductile metals can use yield and tensile strength. Brittle ceramics/semiconductors and anisotropic composites require fracture, flexural or directional strength descriptions instead.

Thermal response

Conductivity, heat capacity and expansion are temperature dependent. The last column is a melting or transition descriptor only where that physical concept is appropriate.

Technical sources

The database favors manufacturer, industry, government or academic technical references and labels secondary condition-specific datasets when a primary source does not expose a complete property set.

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