Introduction
Alumina tubes have good thermal shock and good strength & chemical resistance. Alumina is compatible with platinum thermocouples for long term use in reducing or oxidizing atmospheres and should be used at temperature above 1200°C.
For Temperature Sensing
Alumina thermocouple protection tubes |
Closed one end |
Alumina insulators for thermocouples, thermistors |
Single or Multi-bore tubing used to insulate wires |
Property
Composition | 99.8% Al2O3 |
Bulk Density g/cm3 | 3.8 |
Flexural Strength MPa | 345 |
Compressive Strength MPa | 2650 |
Coeff of Thermal Exp (1000°C) | 8x10-6 |
Thermal Conductivity (1200°C) W/m°K | 8 |
Permeability | Gas tight |
Hardness GPa | 14.0-15.0 |
Features
- Service temerature Up to 1870°C (3400°F) when properly supported
- Fair resistance to thermal and mechanical shock
- Superior resistance to reducing atmospheres
- Induction melting, vacuum furnaces and glass manufacturing
- Impervious to gases at high temperatures
Application
- Iron, barium, crown glass
- non-ferrous metals
- gas-tight protection for noble metal thermocouples in excess of 2400°F (1316°C)