Synthetic Sapphire vs. Zirconia
Both synthetic sapphire and zirconia are oxide-based engineering ceramics. There are 21 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 zirconia.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 2700 | |
| 1260 to 3080 |
| Elastic (Young's, Tensile) Modulus, GPa | 450 | |
| 190 to 200 |
| Flexural Strength, MPa | 1090 | |
| 630 to 970 |
| Fracture Toughness, MPa-m1/2 | 1.9 | |
| 8.0 to 11 |
| Knoop Hardness | 1860 | |
| 1210 to 1300 |
| Poisson's Ratio | 0.28 | |
| 0.25 to 0.29 |
| Tensile Strength: Ultimate (UTS), MPa | 2470 | |
| 410 to 450 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 2000 | |
| 500 to 1330 |
| Specific Heat Capacity, J/kg-K | 760 | |
| 400 to 510 |
| Thermal Conductivity, W/m-K | 30 | |
| 2.2 to 4.3 |
| Thermal Expansion, µm/m-K | 5.3 | |
| 8.8 to 9.5 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 10 | |
| 28 |
| Dielectric Strength (Breakdown Potential), kV/mm | 9.9 | |
| 7.7 to 9.0 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 17 | |
| 4.5 to 11 |
Otherwise Unclassified Properties
| Density, g/cm3 | 4.0 | |
| 5.7 to 6.0 |
Common Calculations
| Stiffness to Weight: Axial, points | 63 | |
| 19 |
| Stiffness to Weight: Bending, points | 64 | |
| 33 to 34 |
| Strength to Weight: Axial, points | 170 | |
| 19 to 22 |
| Strength to Weight: Bending, points | 100 | |
| 21 to 23 |
| Thermal Diffusivity, mm2/s | 9.9 | |
| 0.73 to 1.8 |
| Thermal Shock Resistance, points | 74 | |
| 15 to 19 |