Synthetic Sapphire vs. Limestone
Synthetic sapphire belongs to the oxide-based engineering ceramics classification, while limestone belongs to the natural stone. There are 17 material properties with values for both materials. Properties with values for just one material (8, in this case) are not shown.
For each property being compared, the top bar is synthetic sapphire and the bottom bar is limestone.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 2700 | |
| 700 |
| Elastic (Young's, Tensile) Modulus, GPa | 450 | |
| 77 |
| Poisson's Ratio | 0.28 | |
| 0.25 |
| Shear Modulus, GPa | 150 | |
| 30 |
| Tensile Strength: Ultimate (UTS), MPa | 2470 | |
| 100 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 2000 | |
| 360 |
| Specific Heat Capacity, J/kg-K | 760 | |
| 920 |
| Thermal Conductivity, W/m-K | 30 | |
| 2.1 |
| Thermal Expansion, µm/m-K | 5.3 | |
| 8.0 |
Electrical Properties
| Dielectric Strength (Breakdown Potential), kV/mm | 9.9 | |
| 8.0 |
Otherwise Unclassified Properties
| Density, g/cm3 | 4.0 | |
| 2.6 |
Common Calculations
| Stiffness to Weight: Axial, points | 63 | |
| 16 |
| Stiffness to Weight: Bending, points | 64 | |
| 55 |
| Strength to Weight: Axial, points | 170 | |
| 11 |
| Strength to Weight: Bending, points | 100 | |
| 18 |
| Thermal Diffusivity, mm2/s | 9.9 | |
| 0.88 |
| Thermal Shock Resistance, points | 74 | |
| 12 |