Mullite consists of aluminium oxide (Al2O3) and silicon dioxide (SiO2) with the nominal
composition of 3 Al2O3, 2 SiO2. It offers numerous advantages, including:
- Oxidation resistance
- Good wear resistance
- Low creep
- Low thermal expansion coefficient
- Good thermal shock resistance
- Low-cost refractory compared to high-purity alumina, zirconia, and magnesia
Typical applications for mullite include:
- High-temperature protection tubes
- Kiln furniture
- Electrical insulators/substrates
- Engineering ceramics in turbine engine parts
- Infrared-transmitting windows
Material Properties
Please note that the information set forth herein is offered for comparison only, and is not to be construed as absolute engineering data or constituting a warranty or representation for which we assume legal responsibility.
| — | — | Typical Value |
|---|---|---|
| Purity | — | Al2O3 wt%: 71 .8一77.3 |
| Density (g/cm3) | — | 2.9 |
| Volume resistivity (Ω・cm） | — | 10(13) |
| Max. Working Temperature (℃) | Air | Limit: 1500 Continuous working temperature: 1350 |
| — | Inert Gas (Ar, N2) | 1350 |
| — | Vacuum | 1350 |
| Flexural Strength (MPa) | — | 170-200 |
| Compressive Strength (MPa) | — | >500 |
| Coefficient Of Thermal Expansion, 10(-6)/K, room temperature to 1000 ℃ | — | 4.5-5.5 |
| Thermal Conductivity (W/m*K) | 4.0-6.0 (100-1400 ℃) |
- DATA MEASUREMENTS – All data measurements are typical and made at room temperature unless otherwise noted.
- THERMAL SHOCK RESISTANCE – Tests are run by quenching samples into water from various elevated temperatures. The change in temperature where a sharp decrease in flexural strength is observed is listed as ‘delta Tc’.
- CHEMICAL RESISTANCE – Although all alumina and zirconia ceramics are highly resistant to chemical attack, it is recommended that specific applications are discussed with Almath Crucibles to ensure optimum ceramic selection.
Browse our full range of mullite products
ALMATH
Almath are a globally recognised producer and distributor of high purity crucibles and refractory products.
Company registration no: 3167902 (Incorporated 1996).
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