Zircon FUSED
Grade
FUSED = fused-cast / electrofused zircon
Choose for glass-furnace throat and paver blocks or high-grade refractory grain where maximum density and glass-corrosion resistance are required.
Values for the FUSED condition
Other Zircon tempers and conditions
Zircon is listed in 4 conditions; see the grade overview at Zircon.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Bonded zircon refractory brick / shape | Choose for glass-tank paving, ladle and slide-gate refractories where slag/glass corrosion resistance matters more than strength. | — | — | — | 900 HV | 3 W/m·K |
FUSEDThis page Fused-cast / electrofused zircon | Choose for glass-furnace throat and paver blocks or high-grade refractory grain where maximum density and glass-corrosion resistance are required. | — | — | — | 1,100 HV | 4 W/m·K |
C728Default Dense sintered zircon porcelain | Choose for gas-tight, high-strength electrical/thermal ceramic parts: insulators, nozzles, thermocouple sheaths, foundry tooling. | — | — | — | 1,150 HV | 5 W/m·K |
Zircon sand / milled zircon flour | Choose as raw material: ceramic-glaze opacifier, investment-casting facecoat and foundry sand, or feedstock for zirconia production. | — | — | 0 | 1,200 HV | 5 W/m·K |
What is Zircon FUSED?
Zircon FUSED is Zircon in the FUSED grade — choose for glass-furnace throat and paver blocks or high-grade refractory grain where maximum density and glass-corrosion resistance are required. Zircon FUSED has a tensile strength of 80 MPa (11.6 ksi), weaker than 53% of ceramic grades. The elastic modulus is 150 GPa (21.8 Msi). Zircon FUSED has a density of 4.1 g/cm³ (0.148 lb/in³), lighter than 57% of ceramic grades. It melts at 1,687°C (3,069 °F). C728 is the default condition FabDigit quotes; FUSED is available on request or by drawing note.
Advantages
- High service temperature — 1,650°C (3,002 °F), better than 88% of ceramic grades
- Good corrosion resistance — 92/100, better than 88% of ceramic grades
- Low embodied carbon — 3 kg CO₂/kg, better than 88% of ceramic grades
Zircon FUSED properties
Typical room-temperature values for Zircon FUSED; 10 are specific to this condition. Other listed values are Zircon reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical4
Zircon FUSED has a density of 4.1 g/cm³ (0.148 lb/in³), lighter than 57% of ceramic grades. It melts at 1,687°C (3,069 °F).
Mechanical11
Zircon FUSED has a tensile strength of 80 MPa (11.6 ksi), weaker than 53% of ceramic grades. The elastic modulus is 150 GPa (21.8 Msi).
Thermal5
Zircon FUSED is rated for continuous service to 1,650°C (3,002 °F). It conducts heat at 4 W/m·K (2.31 BTU/hr·ft·°F), worse than 68% of ceramic grades. Thermal expansion is 4.2 µm/m·K (2.33 µin/in·°F).
Electrical5
Zircon FUSED is an electrical insulator with a dielectric strength of 12 kV/mm (304.8 V/mil) and a resistivity of 1×10¹¹ Ω·m.
Chemical & Environmental2
Corrosion resistance is excellent (92/100), better than 88% of ceramic grades.
Sustainability4
Producing a kilogram of Zircon FUSED takes about 40 MJ of energy and emits 3 kg of CO₂ — less than 88% of ceramic grades. Typical recycled content is 3%.
Manufacturability3
Zircon FUSED's machinability is not recommended (4/100, worse than 85% of ceramic grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Zircon FUSED
Is Zircon easy to machine?
Green or bisque bodies machine easily with carbide tooling; after firing only diamond grinding, lapping and ultrasonic/laser machining are practical.
Can Zircon be welded?
Not weldable — join by ceramic-to-metal brazing (Mo-Mn metallizing), glass frit sealing or high-temperature cements.
Can Zircon be formed, bent or molded?
Formed by dry pressing, isostatic pressing, slip casting or extrusion of milled zircon flour with clay/binder, then fired at 1500–1700 °C; allow ~12–18 % firing shrinkage.
What surface finishes work on Zircon?
Diamond grind and polish for sealing faces; glazing improves surface sealing and thermal-shock-crack resistance; no plating or anodizing applies.
Zircon chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| ZrO2ZrO2+HfO2 basis; stoichiometric ZrSiO4 = 67.2 % ZrO2 | 64 – 67.2 | 66 |
| HfO2naturally substitutes for Zr; usually reported inside ZrO2 | 0.8 – 1.8 | 1.2 |
| TiO2impurity from rutile | ≤ 0.2 | 0.08 |
| Fe2O3impurity | ≤ 0.15 | 0.05 |
| Al2O3impurity / bond phase | ≤ 0.6 | 0.25 |
| U+Th (trace)natural radionuclides — relevant to NORM handling rules | ≤ 0.05 | 0.02 |
| SiO2stoichiometric 32.8 % | ≥ 31.5 (balance) | — |
Zircon FUSED — frequently asked
What is Zircon FUSED used for?
Zircon FUSED is typically used for foundry sand/refractories, ceramic glaze opacifier, kiln furniture, investment casting shell and raw material for ZrO2 production. In short: low-expansion refractory silicate; 1500 °C service capability; feedstock for zirconia.
What is the tensile strength of Zircon FUSED?
Zircon FUSED has a typical tensile strength of 80 MPa (11.6 ksi) — weaker than 53% of ceramic grades. Strength varies by condition: see the 4 listed tempers.
Is Zircon FUSED easy to machine?
Not especially — machinability is rated not recommended (4/100, worse than 85% of ceramic grades). Green or bisque bodies machine easily with carbide tooling; after firing only diamond grinding, lapping and ultrasonic/laser machining are practical.
Can Zircon FUSED be welded?
Not weldable — join by ceramic-to-metal brazing (Mo-Mn metallizing), glass frit sealing or high-temperature cements.
What surface finishes work on Zircon FUSED?
Diamond grind and polish for sealing faces; glazing improves surface sealing and thermal-shock-crack resistance; no plating or anodizing applies.
Can Zircon FUSED be formed, bent or molded?
Formed by dry pressing, isostatic pressing, slip casting or extrusion of milled zircon flour with clay/binder, then fired at 1500–1700 °C; allow ~12–18 % firing shrinkage.
What is the maximum service temperature of Zircon FUSED?
Zircon FUSED is rated for continuous use to about 1,650°C (3,002 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ANSI/ASTM C728 — Standard Specification for Zircon Porcelain (technical ceramic classification) — ASTM International (2019)
- ASM Engineered Materials Handbook, Vol. 4: Ceramics and Glasses — ASM International (1991)
- Handbook of Refractory Practice / Refractories Handbook (zircon and zircon-bonded products) — Harbison-Walker / CRC (2005)
- GB/T 21114 — X (used for zircon assay); GB/T industry grades — SAC (2019)
- Technical zircon ceramic and fused-cast zircon datasheets — CoorsTek / Saint-Gobain / Iluka Resources (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.