Chrome Oxide Coatings (Cr2O3 Coatings)
Chrome Oxide Plasma Spray
Food Processing Impeller Shaft Ceramic Coated Seal Surfaces
Chromium oxide coatings, or black oxide coatings, are a type of industrial coating that are applied using flame spray or plasma electric arc coating processes. These types of coatings are highly effective as seal surfaces, as well as improving abrasion and wear resistance. Chrome oxide coatings also have excellent self-mating and anti-galling properties. This material is recommended for resistance to wear by abrasive grains, hard surfaces, particle erosion and cavitation, all at temperatures below 540 ̊C (1,000 ̊F).
Chromium Oxide Applied by Plasma Spray Technology
Plasma spraying is generally regarded as the most versatile of all the thermal spray processes. During operation, gases such as argon and hydrogen are passed through a torch. An electric arc dissociates and ionizes the gases. Beyond the nozzle, the atomic components recombine, giving off a tremendous amount of heat. Within this process the plasma core temperatures are typically greater than 10,000° C, well above the melting temperature of any material.
The plasma spray process uses inert gases fed past an electrode inducing the "plasma" state of the gases. When the gases exit the nozzle of the gun apparatus and return to their normal state, a tremendous amount of heat is released. A powder coating material is injected into the plasma "flame" and propelled onto the substrate.
Chromium Oxide Coating Features
Chrome oxide (Cr2O3) is an inorganic compound of chromium and oxygen. It is one of the principal oxides of chromium and occurs naturally as the rare mineral eskolaite. Chromium oxide coatings (Cr203 coatings) impart many of the material’s favorable characteristics to coated substrates, including:
- Excellent Wear
- Excellent Abrasion Resistance
- High Chemical Resistance
Chromium Oxide Coating Processes
If you are looking for plasma spray coatings that provide excellent self-mating, anti-galling and corrosion resistant properties, plasma sprayed chromium oxide coatings are the perfect choice. Parts that are affected by wear problems caused by cavitation, particle erosion, hard surfaces and abrasive grains are excellent candidates for this material. Our chrome oxide coatings are custom-tailored to your application’s specific requirements using our custom coating processes, which include:
- Plasma Electric Arc
- Powder Feedstock
- Powder Combustion Thermal Spray
- Ceramic-Based Feedstock
ASB provides pre-machining and post finishing to OE dimensions for our chrome oxide coatings, using diamond grinding wheels and diamond belts. Diamond grinding achieves smooth, polished surfaces on Cr2O3, with a low coefficient of friction.
In addition, specialty chemistries, including fused and crushed mixtures or cladded oxide with titanium dioxide additives, are also available to meet unique needs.
Chromium Oxide Cr203 Coating Applications
Due to its color chrome oxide is often referred to as a green or black oxide coating. Chrome oxide coatings are useful in a wide range of additional industrial applications, including:
- Sealing surfaces on food processing equipment
- Enhancing different types of seals
- Improving abrasion and wear resistance
- Bearing protection from long wearing surfaces
Additionally, chrome oxide coatings are commonly applied to pump components, rotating equipment, and other parts and components to improve wear resistance and chemical resistance.