Alumina vs. CVD Diamond
Alumina belongs to the oxide-based engineering ceramics classification, while CVD diamond 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 alumina and the bottom bar is CVD diamond.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 to 370 | |
| 1050 |
| Fracture Toughness, MPa-m1/2 | 3.7 to 7.2 | |
| 5.5 |
| Poisson's Ratio | 0.22 to 0.24 | |
| 0.1 |
| Tensile Strength: Ultimate (UTS), MPa | 210 to 290 | |
| 750 |
Thermal Properties
| Specific Heat Capacity, J/kg-K | 870 to 940 | |
| 500 |
| Thermal Conductivity, W/m-K | 14 to 30 | |
| 1900 |
| Thermal Expansion, µm/m-K | 6.7 to 8.2 | |
| 1.0 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 7.8 to 11 | |
| 5.7 |
| Electrical Dissipation At 1 MHz | 0.00049 to 0.0013 | |
| 0.00020 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 6.2 to 14 | |
| 13 |
Otherwise Unclassified Properties
| Density, g/cm3 | 3.4 to 4.1 | |
| 3.5 |
Common Calculations
| Stiffness to Weight: Axial, points | 35 to 53 | |
| 170 |
| Stiffness to Weight: Bending, points | 57 to 62 | |
| 96 |
| Strength to Weight: Axial, points | 14 to 23 | |
| 59 |
| Strength to Weight: Bending, points | 19 to 28 | |
| 52 |
| Thermal Diffusivity, mm2/s | 3.7 to 10 | |
| 1080 |
| Thermal Shock Resistance, points | 4.9 to 14 | |
| 51 |