Optical Silicon vs. Engineering Porcelain
Optical silicon belongs to the non-glass optical ceramics classification, while engineering porcelain belongs to the oxide-based engineering ceramics. There are 20 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 optical silicon and the bottom bar is engineering porcelain.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 120 | |
| 590 |
| Elastic (Young's, Tensile) Modulus, GPa | 150 | |
| 67 to 150 |
| Flexural Strength, MPa | 300 | |
| 43 to 160 |
| Fracture Toughness, MPa-m1/2 | 3.5 | |
| 2.0 |
| Knoop Hardness | 1130 | |
| 600 |
| Poisson's Ratio | 0.28 | |
| 0.17 |
| Shear Modulus, GPa | 80 | |
| 34 |
| Tensile Strength: Ultimate (UTS), MPa | 110 | |
| 130 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 1350 | |
| 1170 |
| Specific Heat Capacity, J/kg-K | 700 | |
| 600 to 1000 |
| Thermal Conductivity, W/m-K | 150 | |
| 1.8 to 6.5 |
| Thermal Expansion, µm/m-K | 3.0 | |
| 2.0 to 6.6 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 12 | |
| 6.5 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.3 | |
| 2.3 to 3.0 |
Common Calculations
| Stiffness to Weight: Axial, points | 35 | |
| 16 to 29 |
| Stiffness to Weight: Bending, points | 75 | |
| 49 to 65 |
| Strength to Weight: Axial, points | 13 | |
| 12 to 16 |
| Strength to Weight: Bending, points | 22 | |
| 19 to 25 |
| Thermal Diffusivity, mm2/s | 93 | |
| 0.73 to 3.9 |
| Thermal Shock Resistance, points | 18 | |
| 11 to 53 |