Silicon Nitride vs. Cordierite

Silicon nitride belongs to the non-oxide engineering ceramics classification, while cordierite belongs to the oxide-based engineering ceramics. There are 16 material properties with values for both materials. Properties with values for just one material (5, in this case) are not shown.

For each property being compared, the top bar is silicon nitride and the bottom bar is cordierite.

Silicon Nitride (Si₃N₄)Cordierite

Metric UnitsUS Customary Units

Mechanical Properties

Compressive (Crushing) Strength, MPa		600 to 2950
Compressive (Crushing) Strength, MPa		420

Elastic (Young's, Tensile) Modulus, GPa		140 to 310
Elastic (Young's, Tensile) Modulus, GPa		62

Flexural Strength, MPa		130 to 810
Flexural Strength, MPa		17 to 32

Fracture Toughness, MPa-m^1/2		3.1 to 6.2
Fracture Toughness, MPa-m^1/2		2.0

Thermal Properties

Maximum Temperature: Mechanical, °C		1000 to 1330
Maximum Temperature: Mechanical, °C		1150

Maximum Thermal Shock, °C		290 to 750
Maximum Thermal Shock, °C		290 to 390

Specific Heat Capacity, J/kg-K		720 to 800
Specific Heat Capacity, J/kg-K		800 to 850

Thermal Conductivity, W/m-K		12 to 31
Thermal Conductivity, W/m-K		1.3 to 1.7

Thermal Expansion, µm/m-K		2.5 to 3.2
Thermal Expansion, µm/m-K		2.9 to 4.8

Electrical Properties

Dielectric Constant (Relative Permittivity) At 1 MHz		8.0 to 10
Dielectric Constant (Relative Permittivity) At 1 MHz		4.7

Dielectric Strength (Breakdown Potential), kV/mm		18
Dielectric Strength (Breakdown Potential), kV/mm		7.7

Electrical Resistivity Order of Magnitude, 10^x Ω-m		11 to 12
Electrical Resistivity Order of Magnitude, 10^x Ω-m		9.5

Otherwise Unclassified Properties

Density, g/cm³		2.2 to 3.4
Density, g/cm³		2.0 to 2.2

Common Calculations

Stiffness to Weight: Axial, points		34 to 53
Stiffness to Weight: Axial, points		15 to 17

Stiffness to Weight: Bending, points		65 to 78
Stiffness to Weight: Bending, points		59 to 67

Thermal Diffusivity, mm²/s		7.5 to 13
Thermal Diffusivity, mm²/s		0.74 to 1.0