Synthetic Sapphire vs. Grade A Lava
Both synthetic sapphire and grade A lava are oxide-based engineering ceramics. There are 13 material properties with values for both materials. Properties with values for just one material (14, in this case) are not shown.
For each property being compared, the top bar is synthetic sapphire and the bottom bar is grade A lava.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 2700 | |
| 76 to 170 |
| Flexural Strength, MPa | 1090 | |
| 28 to 69 |
| Tensile Strength: Ultimate (UTS), MPa | 2470 | |
| 6.9 to 21 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 2000 | |
| 650 to 1130 |
| Specific Heat Capacity, J/kg-K | 760 | |
| 840 |
| Thermal Conductivity, W/m-K | 30 | |
| 2.0 |
| Thermal Expansion, µm/m-K | 5.3 | |
| 2.5 to 3.3 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 10 | |
| 5.3 to 5.8 |
| Dielectric Strength (Breakdown Potential), kV/mm | 9.9 | |
| 3.2 to 3.9 |
Otherwise Unclassified Properties
| Density, g/cm3 | 4.0 | |
| 2.3 to 2.5 |
Common Calculations
| Strength to Weight: Axial, points | 170 | |
| 0.77 to 2.5 |
| Strength to Weight: Bending, points | 100 | |
| 3.2 to 7.3 |
| Thermal Diffusivity, mm2/s | 9.9 | |
| 1.0 |