Oxide ceramic coatings are inorganic coatings made from metal oxides. Applied to metal parts, they improve wear resistance, corrosion protection, thermal insulation, electrical insulation and chemical stability.
Common oxide ceramics
| Material | Key properties |
|---|---|
| Aluminum oxide (Al₂O₃) | High hardness, wear and corrosion resistance, electrical insulation |
| Chromium oxide (Cr₂O₃) | Superior wear and chemical resistance, high hardness (62–70 HRC) |
| Zirconium oxide (ZrO₂) | Excellent thermal barrier, high toughness, chemical stability |
| Titanium dioxide (TiO₂) | Moderate wear resistance, good lubricity; often blended with other oxides |
| Yttrium oxide (Y₂O₃) | High thermal and erosion resistance, chemical stability |
There are many more, and oxides are often blended to combine properties.
Key properties
- Corrosion resistance: protects against chemical and environmental attack, including marine and industrial settings.
- Thermal barrier: low thermal conductivity (zirconia, for example) for turbine blades and engine components.
- Electrical insulation: alumina provides dielectric strength of 300–400 volts per .001″ of thickness, used on motor housings and non-conductive rollers.
- Chemical stability: resists acids, alkalis and other corrosives. Performance varies by oxide; titanium dioxide, for example, is less resistant to alkalis.
- Wear resistance: high hardness, such as chromium oxide at 62–70 HRC, resists abrasion and erosion.
How we apply ceramics
- Preparation: we clean and roughen the surface for strong adhesion.
- Material: the oxide your specification calls for, such as alumina for wear resistance or zirconia for thermal protection.
- Plasma spraying: ceramic powder melts in a plasma jet (up to 30,000 °F) and builds a uniform, high-density coating.
- Finishing: we diamond grind, diamond lap or diamond super finish to your specifications in our Allentown shop; ceramics can be lapped to a 4 Ra finish.
Where they’re used
- Energy sector components, including boiler tubes and turbine blades
- Steel and metal processing
- Industrial pump and seal systems
- Aerospace components
- Contamination-sensitive equipment: see how we ceramic-coated a battery maker’s spray dryer