China Refractory Furnace Tube Industrial Alumina Ceramic Tube, Find details about China Alumina Ceramic Tube, Alumina Ceramic from Refractory Furnace Tube Industrial Alumina Ceramic Tube
With good thermostability,corrosion resistence,thermal shock resistance,high mechanical strength,excellent electrical property etc,ceramic parts are widely used in industrial epuipment manufacturing industries.
All products through the German DIN standards: DIN43724 / DIN43725 / DIN40680
We only make high purity alumina ceramics
1. High-purity alumina content 99.3% -99.5%, other alumina ceramics 92% -99%.
2. The color of high purity alumina product is milky white, and other products are pink or white. The higher the purity, the more transparent the color.
3. Alumina is a refractory material, the higher the purity, the better the refractory effect.
4. After high-purity alumina ceramics are fired and cooled in a 1800-degree high-temperature kiln, the products are not easy to break when they encounter high temperatures. Other ceramics are fired at 1500 ºC ~ 1800 ºC.
5. The volume density of high-purity alumina> 3.92 g / cm3 has a smooth surface and is not easily corroded by chemicals. The bulk density of other ceramics is> 3.70 g / cm3 ~> 3.85 g / cm3.
6. High purity alumina has good hardness and good wear resistance.
7. High purity alumina products have a longer service life.
NAME | CONTENT(%) |
Al2O3 | 99.3-99.5(99.7) |
SiO2 | 0.3-0.5 |
CaO+MgO | 0.2-0.3 |
K2O+Na2O | 0.2-0.35 |
Fe2O3 | <0.1 |
OTHER | <0.05 |
NO. | Property | Unit | Alumina |
1 | Al2O3 | % | >99.3 |
2 | SiO2 | % | - |
3 | Density | g/cm3 | 3.88 |
4 | Water absorption | % | 0.01 |
5 | Cold compressive strength | MPa | 350 |
6 | 20ºC leakage rates | Torr/L.sec | <10-11 |
7 | Twisting in high temperature | mm | 0.2 allowed in 1600ºC |
8 | Bonding in high temperature |
| not bonded in 1600ºC |
9 | 20-1000ºC coefficient ofthermalexpansion | mm.10-6/ºC.m | 8.2 |
10 | Thermal conductivity | W/m.k | 25 |
11 | Electric insulation strength | KV/mm | 20 |
12 | 20ºCdirect current insulation resistance | Ohm/cm | 1014 |
13 | High-temperature insulation resistance | 1000ºC MΩ | ≥0.08 |
1300ºC MΩ | ≥0.02 | ||
14 | Thermal shock resistance |
| 4 times not cracked in 1550ºC |
15 | Maximum working temperature | ºC | 1800 |