ER 1681® RN

Fused cast

Regular cast, electrofused Alumina-Zirconia-Silica (AZS) with 32% zirconia


Good castability Alumina-Zirconia-Silica (AZS) enabling complex and varied shapes and sizes.

Typical application

The regular cast, electrofused Alumina-Zirconia-Silica (AZS) with 32% zirconia, ER 1681 RN is used in a very large range of applications:

  • superstructures, including crowns
  • glass-contact working end and feeders for sodalime and insulation glass fiber
  • available with TuckPro solution

Discover TuckPro solution

Chemical and physical properties


Microstructure of ER 1681

Typical chemical composition


Typical crystallographic analysis


Physical characteristics

Description International standards British standards
Refractoriness under load of 2.105 Pa (2kg/cm²) 1,700°C 3,092°F
Cold crushing strength ≥350Mpa ≥50,763psi
Typical bulk density 3.5g/cm3 218pcf

Thermal conductivity curve

0123456789101102004006008001,0001,2001,4001,6001,800Thermal conductivity (W/(mK)Temperature (°C)

Electrical resistivity curve

Temperature (°C)Electrical resistivity (ohm-cm)800.00710.00900.00500.001,000.00370.001,100.00220.001,200.00160.001,300.00120.001,400.00110.001,500.0090.001,600.0081.00ER 16811101001,00010,0008009001,0001,1001,2001,3001,4001,5001,600Electrical resistivity (ohm-cm)Temperature (°C)


The regular cast, electrofused Alumina-Zirconia-Silica (AZS) with 32% zirconia, ER 1681 RN must be stored in a dry environment protected from weather conditions.

Related products

Fused cast

Void-free electrofused alumina-zirconia-silica (AZS) with 32% zirconia

Alumina-zirconia-silica (AZS) with good castability enabling complex and varied shapes and sizes. Void-free structure enabling longer lifetime.

Fused cast

Regular cast electrofused Alumina-Zirconia-Silica (AZS) with 36% zirconia and a low silicate phase (14%)

Low exudation and high creep resistance.
Good resistance to alkali vapour and carry over.

Fused cast

Regular cast, electrofused 95% alumina (alpha-beta alumina)

Excellent glass contact properties with extremely low defect potential.
High resistant to alkali vapor and creep for superstructure application.

Fused cast

Void-free electrofused alumina-zirconia-silica (AZS) with 40% zirconia solution

Alumina-zirconia-silica (AZS) material with highest corrosion resistance and good castability for various shapes and sizes. It is essentially free of casting cavities and allows a very homogeneous internal structure and corrosion resistance.


Sintered high-alumina 93%

High alumina content sintered material. Very good glass contact properties with the low glass defect potential.
Available in complex and large shapes.


Bonded alumina-zirconia-silica (AZS) with 10% zirconia

ZA33 is adapted for most of the standard feeder expendable applications.