Mullite vs. Hexagonal Boron Nitride
Mullite belongs to the oxide-based engineering ceramics classification, while hexagonal boron nitride belongs to the non-oxide engineering ceramics. There are 16 material properties with values for both materials. Properties with values for just one material (10, in this case) are not shown.
For each property being compared, the top bar is mullite and the bottom bar is hexagonal boron nitride.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 800 | |
| 21 to 250 |
| Elastic (Young's, Tensile) Modulus, GPa | 110 to 170 | |
| 14 to 60 |
| Flexural Strength, MPa | 130 to 160 | |
| 18 to 140 |
| Poisson's Ratio | 0.25 | |
| 0.11 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 1680 | |
| 1030 to 2350 |
| Specific Heat Capacity, J/kg-K | 950 | |
| 840 to 1610 |
| Thermal Conductivity, W/m-K | 3.5 to 11 | |
| 29 to 96 |
| Thermal Expansion, µm/m-K | 5.8 | |
| 0.54 to 18 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 6.3 | |
| 4.0 to 4.4 |
| Dielectric Strength (Breakdown Potential), kV/mm | 16 to 17 | |
| 61 to 200 |
| Electrical Dissipation At 1 MHz | 0.0025 | |
| 0.00075 to 0.0018 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 10 to 11 | |
| 13 to 15 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.7 to 3.0 | |
| 1.9 to 2.1 |
Common Calculations
| Stiffness to Weight: Axial, points | 22 to 31 | |
| 4.1 to 18 |
| Stiffness to Weight: Bending, points | 58 to 62 | |
| 42 to 69 |
| Thermal Diffusivity, mm2/s | 1.4 to 3.7 | |
| 9.9 to 34 |