Synthetic Sapphire vs. Aluminum Nitride
Synthetic sapphire belongs to the oxide-based engineering ceramics classification, while aluminum nitride belongs to the non-oxide engineering ceramics. There are 17 material properties with values for both materials. Properties with values for just one material (11, in this case) are not shown.
For each property being compared, the top bar is synthetic sapphire and the bottom bar is aluminum nitride.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 2700 | |
| 2100 |
| Elastic (Young's, Tensile) Modulus, GPa | 450 | |
| 330 |
| Flexural Strength, MPa | 1090 | |
| 190 to 400 |
| Fracture Toughness, MPa-m1/2 | 1.9 | |
| 2.9 |
| Knoop Hardness | 1860 | |
| 1160 |
| Poisson's Ratio | 0.28 | |
| 0.21 to 0.31 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 2000 | |
| 1380 |
| Specific Heat Capacity, J/kg-K | 760 | |
| 780 |
| Thermal Conductivity, W/m-K | 30 | |
| 80 to 190 |
| Thermal Expansion, µm/m-K | 5.3 | |
| 4.2 to 5.4 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 10 | |
| 6.9 to 28 |
| Dielectric Strength (Breakdown Potential), kV/mm | 9.9 | |
| 15 to 56 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 17 | |
| 10 to 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 4.0 | |
| 2.9 to 3.3 |
Common Calculations
| Stiffness to Weight: Axial, points | 63 | |
| 55 to 63 |
| Stiffness to Weight: Bending, points | 64 | |
| 69 to 80 |
| Thermal Diffusivity, mm2/s | 9.9 | |
| 31 to 74 |