Optical Silicon vs. Aluminum Nitride
Optical silicon belongs to the non-glass optical ceramics classification, while aluminum nitride belongs to the non-oxide engineering ceramics. There are 15 material properties with values for both materials. Properties with values for just one material (13, in this case) are not shown.
For each property being compared, the top bar is optical silicon and the bottom bar is aluminum nitride.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 120 | |
| 2100 |
| Elastic (Young's, Tensile) Modulus, GPa | 150 | |
| 330 |
| Flexural Strength, MPa | 300 | |
| 190 to 400 |
| Fracture Toughness, MPa-m1/2 | 3.5 | |
| 2.9 |
| Knoop Hardness | 1130 | |
| 1160 |
| Poisson's Ratio | 0.28 | |
| 0.21 to 0.31 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 1350 | |
| 1380 |
| Specific Heat Capacity, J/kg-K | 700 | |
| 780 |
| Thermal Conductivity, W/m-K | 150 | |
| 80 to 190 |
| Thermal Expansion, µm/m-K | 3.0 | |
| 4.2 to 5.4 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 12 | |
| 6.9 to 28 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.3 | |
| 2.9 to 3.3 |
Common Calculations
| Stiffness to Weight: Axial, points | 35 | |
| 55 to 63 |
| Stiffness to Weight: Bending, points | 75 | |
| 69 to 80 |
| Thermal Diffusivity, mm2/s | 93 | |
| 31 to 74 |