Introduction Alumina ceramic porous electrical insulator
Alumina ceramic insulator(especially high alumina ceramic) for electrical industry is used for many decades as insulators or enclosures for electrical components. Additionally, it has been incorporated into many appliance, aerospace and automotive applications where moderate strength, low cost and good electrical resistance are required. This ceramic material can be formed into complex shapes prior to sintering, which has led to wide usage in a variety of applications.
Characteristics Alumina ceramic porous electrical insulator
Physical Properties
- Relatively high mechanical strength
- High volume resistivity at elevated temperatures
- Excellent dielectric strength
- Low dissipation factor
- High alumina ceramic
Applications
- Supports for heating elements
- Electrical insulators
- Stand-off insulators
- Lighting insulators (supports, bases, etc.)
- Spacers
- Insulating washers or bushings
Technical Data Sheet of Alumina ceramic porous electrical insulator
| Item | Test condition | Unit | 96% alumina ceramics | 99% alumina ceramics | 99.5-99.7% alumina ceramics |
| Chemical ingredients | Al2O3 | Al2O3 | Al2O3 | ||
| Bulk Density | g/cm3 | >3.6 | 3.88 | 3.90 | |
| Max. Use Temp. | 1450℃ | 1600℃ | 1650℃ | ||
| Water absorption | % | 0 | 0 | 0 | |
| ROHS Hardness | ≥85 | ≥89 | ≥89 | ||
| Flexural strength | 20℃ | Mpa(psix10^3) | 358(52) | 550 | 550 |
| Compressive Strength | 20℃ | Mpa(psix10^3) | 2068(300) | 2600(377) | 2600(377) |
| Fracture Toughness | K(l c) | Mpa m^1/2 | – | – | – |
| Coefficient of thermal expansion | 25-1000℃ | 1X10^-6/℃ | 7.6 | 7.9 | 8.2 |
| Coefficient of thermal conductivity | 20℃ | W/m.K | 16 | 17-30.0 | 17-30.4 |
| Thermal Shock Resistance | ^Tc | ℃ | 250 | 200 | 200 |
| Dielectricity constant | 1MHz.25℃ | 9 | 9.7 | 9.7 | |
| Dielectric strength | ac-kV/mm(ac V/mil) | 8.3(210) | 8.7(220) | 8.7(220) | |
| Volume Resistivity | 100℃ | ohm-cm | >10^13 | >10^14 | >10^14 |
