Sintered dense zircon


High-purity dense zircon. The best thermal shock resistance of any available dense zircon refractory material.

Typical application

ZS78 is used in glass contact areas of the furnace where thermal cycling or gradients cause traditional refractories to crack, thereby affecting refractory life or glass quality. These areas include melter sidewalls (particularly batching areas), bottom paving, refiners, forehearths, flow blocks and bushing blocks. Due to its fine grain structure, ZS78 is an excellent choice for use as bushing blocks in manufacturing very small diameter glass fibers.

ZS78 should also be used wherever seeds or blisters represent a quality problem. Glasses include reinforcement and textile fiber glass, borosilicates, glass ceramics, low-alkali compositions and other technical compositions.

Chemical and physical properties


ZS78 microstructure

Typical chemical composition


Typical crystallographic analysis

Main phase: zircon

Physical characteristics

Description International standards British standards
Cold modulus of rupture 38Mpa 5,511psi
Cold crushing strength 300Mpa 43,511psi
Thermal conductivity at 1,000°C 3.1 W.m-1.K-1

21.5 BTU
in hr-1ft-2°F-1

Porosity 10% 10%
Typical bulk density 4.20g/cm3 262pcf

Expansion curve

Expansion curve sintered ZS78

Thermal conductivity curve

Thermal conductivity curve sintered ZS78


The sintered dense zircon, ZS78 solution must be stored in a dry environment protected from weather conditions.

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