Optical Silicon vs. Carbon-carbon
Optical silicon belongs to the non-glass optical ceramics classification, while carbon-carbon belongs to the non-oxide engineering ceramics. There are 16 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 optical silicon and the bottom bar is carbon-carbon.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 120 | |
| 240 |
| Elastic (Young's, Tensile) Modulus, GPa | 150 | |
| 95 |
| Poisson's Ratio | 0.28 | |
| 0.32 |
| Shear Modulus, GPa | 80 | |
| 36 |
| Tensile Strength: Ultimate (UTS), MPa | 110 | |
| 19 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 1350 | |
| 2400 |
| Specific Heat Capacity, J/kg-K | 700 | |
| 760 |
| Thermal Conductivity, W/m-K | 150 | |
| 40 |
| Thermal Expansion, µm/m-K | 3.0 | |
| 4.0 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.3 | |
| 1.7 |
Common Calculations
| Stiffness to Weight: Axial, points | 35 | |
| 31 |
| Stiffness to Weight: Bending, points | 75 | |
| 89 |
| Strength to Weight: Axial, points | 13 | |
| 3.0 |
| Strength to Weight: Bending, points | 22 | |
| 9.1 |
| Thermal Diffusivity, mm2/s | 93 | |
| 31 |
| Thermal Shock Resistance, points | 18 | |
| 3.5 |