Synthetic Sapphire vs. Soda-lime Glass
Synthetic sapphire belongs to the oxide-based engineering ceramics classification, while soda-lime glass belongs to the glass and glass-ceramics. There are 20 material properties with values for both materials. Properties with values for just one material (5, in this case) are not shown.
For each property being compared, the top bar is synthetic sapphire and the bottom bar is soda-lime glass.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 450 | |
| 70 to 71 |
| Knoop Hardness | 1860 | |
| 570 |
| Poisson's Ratio | 0.28 | |
| 0.23 |
| Shear Modulus, GPa | 150 | |
| 29 |
| Tensile Strength: Ultimate (UTS), MPa | 2470 | |
| 41 to 180 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 2000 | |
| 300 |
| Specific Heat Capacity, J/kg-K | 760 | |
| 720 to 800 |
| Thermal Conductivity, W/m-K | 30 | |
| 1.0 to 1.1 |
| Thermal Expansion, µm/m-K | 5.3 | |
| 8.8 to 9.0 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 10 | |
| 7.3 to 7.4 |
| Dielectric Strength (Breakdown Potential), kV/mm | 9.9 | |
| 13 |
Otherwise Unclassified Properties
| Density, g/cm3 | 4.0 | |
| 2.4 |
| Light Transmission Range, µm | 0.17 to 5.5 | |
| 0.35 to 2.5 |
| Refractive Index | 1.8 | |
| 1.5 |
Common Calculations
| Stiffness to Weight: Axial, points | 63 | |
| 16 |
| Stiffness to Weight: Bending, points | 64 | |
| 56 |
| Strength to Weight: Axial, points | 170 | |
| 4.6 to 20 |
| Strength to Weight: Bending, points | 100 | |
| 11 to 28 |
| Thermal Diffusivity, mm2/s | 9.9 | |
| 0.51 to 0.6 |
| Thermal Shock Resistance, points | 74 | |
| 4.7 to 20 |