• for the coating of ceramics, fibre ceramics, graphite and metals
• good chemical stability
• for high temperature applications up to 1900°C (3452°F)
• contains stabilized zirconium oxide


Zirconia-Coating ZR-A is a special coating based on CaO-stabilized zirconium oxide. Contrary to the frequently used zircon (zirconium silicate) zirconium oxide shows a substantially better stability and temperature stress. Zirconia-Coating ZR-A is preferably used as protection and interface for graphite and ceramic crucibles, refractory bricks and fibre ceramics as well as for coating kiln furniture, supports and trays.

Within the metallurgical field of application Zirconia-Coating ZR-A can be used for coating crucibles, troughs, dies and thermocouples in order to obtain very pure melts and clean casting surfaces.

Due to its small grain size Zirconia-Coating ZR-A can be applied in thin layers (max. 200µm) only. For thicker layers the product Zirconia-Coating ZR-O is available. As an inexpensive version Zirconia-Coating ZR-M is recommended, based on unstabilized zirconium oxide.

Zirconia-Coating ZR-A can be used both at air as well as in the vacuum and inert gas to 1900°C (3452°F). On graphite an application to approximetaly 1500°C (2732°F) is possible.


• Resuspend Zirconia-Coating ZR-A before use. If necessary, dilute with distilled water.
• Product is applied by brushing on clean surfaces.
• Dry carefully. Do not contact wet coatings with metal melts. After drying further coatings can be applied.
• Curing of the coating can take place at 1000°C (1832°F)
• Best performance of Zirconia-Coating ZR-A is obtained by a thin coat (<200µm).
• With a thicker coating application the danger of cracking exists.
• During the application a damage of the coating should be avoided, because damaged areas are no longer sufficiently protected.
• Tools can be cleaned with water.

Storage-Container Size

Keep containers closed and protect against frost. A storage temperature of >5°C (>41°F) is recommended. Zirconia-Coating ZR-A is available in 1kg-containers.

Technical Data



Ceramic Constituent

Zirconium oxide




96%ZrO2 (CaO)


Solid Content



1.8 g/cm³

Temperature (max. Application)

1900°C (3452°F) (at air, vacuum, inert gas)

1550°C (2822°C) (on graphite)


© 2023 Büro für angewandte Mineralogie · Dr. Stephan Rudolph · D-47918 Tönisvorst

These recommendations are believed to be correct. However, no guarantee of their accuracy is given. Therefore, purchasers shall make their own tests to determine suitability for their use. These products are offered for industrial and related uses (e.g. research and development) only. However the user must take the necessary precautions appropriate for products containing chemicals. This description does not imply the absence of any patents, the responsibility whatsoever solely rests with the user.