LOW MASS ZIRCONIA GROG
TYPE ZG
Features
- High Temperature Stability to 2200°C
- Low Thermal Conductivity
- Highly Refractory
- Excellent Thermal Shock Resistance
- No Outgassing
- Two Particle Size Ranges are Offered
- Available 'Off the Shelf'
Zircar Zirconia Low Mass Grog Type ZG is high fired, fibrous yttria-stabilized zirconia particles, ideally suited for thermal insulation under conditions of ultra high temperatures. Type ZG exhibits exceptional resistance to oxidizing and reducing atmospheres at high temperatures. Zirconia, however, loses a small amount of oxygen in inert and reducing atmospheres and in vacuum at very high temperatures. This results in a color change from white to gray; while most other properties remain essentially unchanged and the insulation effectiveness is not impaired. Type ZG Grog offers lower thermal conductivity and specific heat than conventional dense grogs. This makes it useful for crystal growth and glass melting furnace insulation applications.
Type ZG contains no organic binders and will produce no smoke or odor when heated. ZG Grog will conduct electricity at elevated temperatures. Type ZG Grog is available in two standard particle size ranges.
- Type ZG-1 has a Tyler mesh size of -3 1/2 to +8 (5.7mm to 2.4mm)
- Type ZG-2 has a Tyler mesh size of -8 to +14 (2.4mm to 1.2mm)
Application Information
- ZG Grog is used as insulation and crucible support in crystal growing furnaces.
- ZG Grog is used as insulation for glass melting furnaces.
- ZG Grog is used as bulk fill insulation.
Chemical Composition
Zircar Zirconia’s Type ZG is nominally 90 wt% ZrO2 + HfO2 and 10 wt% Y2O3. 1 - 2 wt% hafnia (HfO2) occurs naturally with zirconia (ZrO2) and does not affect performance. Only the highest purity starting materials are used to make Type ZG minimizing trace oxides.
| Trace Oxide | Typical Wt% |
|---|---|
| SiO2 | 0.12 |
| TiO2 | 0.14 |
| CaO | 0.09 |
| MgO | 0.03 |
| Fe2O3 | 0.04 |
| Trace Oxide | Typical Wt% |
|---|---|
| Al2O3 | 0.01 |
| Na2O | 0.01 |
| SnO2 | 0.001 |
| Cr2O3 | 0.0005 |
| Ag2O | 0.0005 |
Properties & Characteristics
| Melting Point, °C (°F) | 2590 (4694) |
| Maximum Use Temperature*, °C (°F) | 2200 (3992) |
| Porosity of Particles, % | 70 |
| Bulk Density, g/cc (pcf) | 0.88 (55) |
| Outgassing | Nil |
| % Shrinkage 1 hour at 1700°C(3092°F) | 0 |
| % Shrinkage 1/2 hour at 2000°C(3632°F) | 2 |
* Maximum use temperature is dependent on variables such as stresses, both thermal and chemical, and the chemical environment that the material experiences
Ordering Information
| Standard Sizes | Item Number |
|---|---|
| ZG-1, -3 1/2 to +8 Tyler, 1 pound | BD001 |
| ZG-1, -3 1/2 to +8 Tyler, 10 pounds | BD002 |
| ZG-2, -8 to +14 Tyler , 1 pound | BE001 |
| ZG-2, -8 to +14 Tyler, 10 pounds | BE002 |
