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Description: WOLLASTONITE
Oxide | Analysis | Formula | |
---|---|---|---|
CaO | 47.50% | 1.00 | |
MgO | 0.10% | - | |
TiO2 | 0.02% | - | |
Al2O3 | 0.20% | - | |
SiO2 | 51.00% | 1.00 | |
Fe2O3 | 0.40% | - | |
MnO | 0.10% | - | |
LOI | 0.68% | n/a | |
Oxide Weight | 116.96 | ||
Formula Weight | 117.76 |
This is a coarser grade of needle-shaped crystal wollastonite that acts in a manner similar to fiber additions.
Adding 3-5% will reduce dry and firing shrinkage and improve impact resistance.
Screens to 60 mesh or coarser will accomodate re-screening. 1% retention of 100 mesh is normal.
Best to add to finished slip during gentle paddle mixing.
Polyacrylate thickeners might interfere with efficiency.
Effects on firing are minimal enough that Nyco recommends post additions.
Morphology: Acicular
Specific Gravity: 2.9
Refractive Index: 1.63
pH (19% slurry): 9.9
Water Solubility (g/100cc): 0.0095
Density (lbs/solid gallons): 24.2
Bulking value (gal/lbs): 0.0413
Mohs hardness: 4.5
Coefficient of expansion (mm/mm/C): 6.5 x 10-6
Median particle size (microns): 45
Minus 100 mesh (%): 97
Moisture (%): 0.01
Typecodes |
Aggregate
Granular materials intended to impart raw and fired structural strength or thermal expansion properties to bodies or deliver special speckling effects in glazes. |
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Frit Softening Point | 1540 C |
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