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| Oxide | Analysis | Formula | Tolerance |
|---|---|---|---|
| CaO | 0.05% | - | |
| K2O | 0.80% | 0.01 | |
| MgO | 0.15% | 0.01 | |
| Na2O | 0.30% | 0.01 | |
| TiO2 | 0.20% | - | |
| Al2O3 | 73.30% | 1.00 | |
| SiO2 | 24.70% | 0.57 | |
| Fe2O3 | 0.50% | - | |
| Oxide Weight | 139.15 | ||
| Formula Weight | 139.15 | ||
A hollow sphere of mullite ceramic, fired at 1740C in sizes of 3.0-5.0mm, 1.5-3.0mm, 0.5-1.5mm. It has very low density, low thermal conductivity and high crushing strength. Its main use is in refractories, but it is also suitable as a bedding material for the firing of delicate ceramic objects of all types.
Refractoriness: 1875/1900C
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