Steatite vs. Synthetic Sapphire
Both steatite and synthetic sapphire are oxide-based engineering ceramics. There are 19 material properties with values for both materials. Properties with values for just one material (10, 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 steatite and the bottom bar is synthetic sapphire.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 540 to 620 | |
| 2700 |
| Elastic (Young's, Tensile) Modulus, GPa | 68 to 120 | |
| 450 |
| Flexural Strength, MPa | 32 to 150 | |
| 1090 |
| Poisson's Ratio | 0.23 | |
| 0.28 |
| Tensile Strength: Ultimate (UTS), MPa | 60 to 220 | |
| 2470 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 750 to 1230 | |
| 2000 |
| Specific Heat Capacity, J/kg-K | 850 to 860 | |
| 760 |
| Thermal Conductivity, W/m-K | 1.8 to 2.5 | |
| 30 |
| Thermal Expansion, µm/m-K | 7.0 to 9.0 | |
| 5.3 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 5.7 to 6.5 | |
| 10 |
| Dielectric Strength (Breakdown Potential), kV/mm | 7.9 to 16 | |
| 9.9 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 8.0 to 11 | |
| 17 |
Otherwise Unclassified Properties
| Density, g/cm3 | 1.9 to 2.8 | |
| 4.0 |
Common Calculations
| Stiffness to Weight: Axial, points | 14 to 32 | |
| 63 |
| Stiffness to Weight: Bending, points | 52 to 83 | |
| 64 |
| Strength to Weight: Axial, points | 6.4 to 32 | |
| 170 |
| Strength to Weight: Bending, points | 13 to 42 | |
| 100 |
| Thermal Diffusivity, mm2/s | 0.79 to 1.1 | |
| 9.9 |
| Thermal Shock Resistance, points | 5.1 to 33 | |
| 74 |