3M Technical Ceramics
Zweigniederlassung der 3M Deutschland GmbH

Chemical properties

Chemical formula ZrB₂
Molecular weight 112.85 g/mol
Crystalline structure hexagonal

Insoluble in water

Physical properties

Specification Weight 6.09 g/cm³
Extreme hardness 8 mohs
  • High electrical conductivity
  • Good resistance to oxidation

Thermal properties

Melting point 3,246 °C
  • Fireproof
  • Good thermal conductivity

Manufacture and form

Zirconium diboride (ZrB2) is manufactured from the raw materials boron oxide, zirconium oxide and carbon in an arc furnace at temperatures above 2400°C. Concurrently, the following reaction takes place:

B₂O₃ + ZrO₂ + 5 C → ZrB₂ + 5 CO

The resultant gray-silver crystals are separated from unreacted material, ground and classified in further preparation steps. Depending on its further use, the material is ground until in the micron range.

Zirconium diboride is used mainly in fireproof applications, for example

  • in ZrO₂-C masses for submerged nozzles and shrouds to improve corrosion resistance (the standard grain size used for this is 400 mesh) and
  • as anti-oxidants in carbon-bonded fireproof ceramics