Materials
Since 1911
| Designation | Sapphire | Al 99.9 | Al 99.7 | TZP-A | ATZ-A | |
|---|---|---|---|---|---|---|
| Components | Al203 | Al203 | Al203 | Zr02/Y203/Al203 | Zr02/Al203/Y203 | |
| Composition | % | 99.998 | 99.9 | 99.7 | 95/5/0.25 | 76/20/4 |
| Density | g/cm3 | 3.98 | 3.90 | 3.86 | 6.05 | 5.5 |
| Open porosity | % | 0 | 0 | 0 | 0 | 0 |
| Grain size | μm | 0 | 1.8 | 5 | 0.35 | 0.4 |
| Hardness Vickers | Hv | 2000/2200 | 2100 | 1900 | 1200 | 1400 |
| Compressive strength | MPa | 2000 | 3800 | 2500 | 2000 | 2000 |
| Flexural strength | MPa | 800/1000 | 500 | 350 | 1100 | 2000 |
| Young’s modulus | Gpa | Pa 4.4.1011 @300K | 380 | 350 | 210 | 220 |
| Fracture toughness K1c | MN/m3/2 | 6 | 4 | 3.5 | 8 | 8 |
| Poisson ratio | - | 0.30 | 0.24 | 0.24 | 0.31 | 0.3 |
| Max. operating temperature | °C | 1600 | 1900 | 1900 | 1000 | 1000 |
| Thermal expansion (20-1000°C) | 10-6/K | 8-9 | 8.0 | 8.0 | 10 | 9 |
| Thermal conductivity | W/mK | 40 | 30 | 29 | 2.5 | 6 |
| Specific heat | J/kg K | 700 | 900 | 900 | 500 | 600 |
| Dielectric strength | KV/mn | 35 | 35 | 30 | - | - |
| Electrical resistivity (20°C/1000°C | Ω cm | 1016 | >1014/109 | 1014/109 | - | - |
