Ceramic materials are applied for their extreme hardness, wear-resistance, chemical resistance and their heat-insulating properties. The two main categories for applying chemical coatings:
The materials for wear-resistant coatings can be split into chrome oxide (Cr2O3) and aluminium oxide (Al2O3); these materials can also be alloyed with titanium oxide (Ti) for more ductile properties. Ceramic coatings are characterised by their low frictional resistance and therefore they are extremely suitable as a running surface for O-rings and retaining rings. These materials are also extremely suitable as a running surface for mechanical seals.
For jet and combustion engines heat-insulating coatings are a must to protect components against the high operating temperatures. Zircon oxide (ZrO2) is often used as the basic coating for high-temperature applications.
Besides its use as a coating on components in jet and combustion engines, the coating is also used in the steel industry for extrusion dies and as protective coating on thermowells.
Another application for aluminium oxide (Al2O3) is forming an electrically insulating coating on bearing cups of roller bearings and other bearings. Bearings can generate static electricity and in some environments they can produce explosion hazards. These coatings are often used in ATEX environments.