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Description: Zirconium Silicate Opacifier
Oxide | Analysis | Formula | |
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HfO2 | 1.30% | 1.09 | |
TiO2 | 0.10% | 0.22 | |
ZrO2 | 64.80% | 92.48 | |
Al2O3 | 0.58% | 1.00 | |
SiO2 | 32.50% | 95.10 | |
Fe2O3 | 0.02% | 0.02 | |
Oxide Weight | 17,463.10 | ||
Formula Weight | 17,463.10 |
The designation 'Plus' refers to the particle size, it is a finer grained version zirconium silicate (also known as Superpax). This material is a more potent opacifier than Zircopax, testing will be required to determine how much less to use when substituting.
It is 5 mm thick (compared to the 17mm of the cordierite one). It weighs 650 grams (vs. 1700 grams). It will perform at any temperature that my test kiln can do, and far in excess of that. It is made from a body I slurry up (80% Zircopax Plus, 16.5% 60-80 Molochite grog, 3.5% Veegum T). The body is plastic and easy to roll and had 4.2% drying shrinkage at 15.3% water. The shelf warped slightly during drying (I should have dried it between sheets of plasterboard). Firing at cone 4 yielded a shrinkage of 1%. Notice that cone on the shelf: It has not stuck even though no kiln wash was used! Zircopax is super refractory! This is sinter bonded, so the higher the temperature you can fire the stronger it will be. Although it would be very hard to make full 18 or 22-inch shelves for larger kilns, smaller ones designed to "network" would enable a tighter load of ware with a much lower shelf-to-ware weight ratio (especially using my own lightweight posts). Like alumina, this does not have the thermal shock resistance of cordierite, uneven heating can crack these.
These bags actually contain Zircopax Plus since Trebol is the new owner of the company.
Materials |
Superpax
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Materials |
Magnesium Zirconium Silicate
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Materials |
Zircopax
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Materials |
Tin Oxide
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Materials |
Zircon
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Materials |
Zircosil
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Materials |
Opax
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Materials |
Ultrox
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Typecodes |
Opacifier
Opacifiers are powders that turn transparent glazes opaque by various chemical and physical mechanisms (and combinations of mechanisms). |
Density (Specific Gravity) | 2550 |
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Glaze Opacifier | Superpax is a very fine grade zirconium silicate opacifier and will produce a whiter result than less expensive grades. See Zircopax. |
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