Synthetic Sapphire vs. Carbon-carbon
Synthetic sapphire belongs to the oxide-based engineering ceramics classification, while carbon-carbon 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. Please note that the two materials have significantly dissimilar densities. This means that additional care is required when interpreting the data, because some material properties are based on units of mass, while others are based on units of area or volume.
For each property being compared, the top bar is synthetic sapphire and the bottom bar is carbon-carbon.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 2700 | |
| 240 |
| Elastic (Young's, Tensile) Modulus, GPa | 450 | |
| 95 |
| Poisson's Ratio | 0.28 | |
| 0.32 |
| Shear Modulus, GPa | 150 | |
| 36 |
| Tensile Strength: Ultimate (UTS), MPa | 2470 | |
| 19 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 2000 | |
| 2400 |
| Specific Heat Capacity, J/kg-K | 760 | |
| 760 |
| Thermal Conductivity, W/m-K | 30 | |
| 40 |
| Thermal Expansion, µm/m-K | 5.3 | |
| 4.0 |
Electrical Properties
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 17 | |
| -5.0 |
Otherwise Unclassified Properties
| Density, g/cm3 | 4.0 | |
| 1.7 |
Common Calculations
| Stiffness to Weight: Axial, points | 63 | |
| 31 |
| Stiffness to Weight: Bending, points | 64 | |
| 89 |
| Strength to Weight: Axial, points | 170 | |
| 3.0 |
| Strength to Weight: Bending, points | 100 | |
| 9.1 |
| Thermal Diffusivity, mm2/s | 9.9 | |
| 31 |
| Thermal Shock Resistance, points | 74 | |
| 3.5 |