Plasma Spraying

The plasma spray process is the most versatile of all the thermal spray processes. During operation, gases such as argon, nitrogen, helium, or hydrogen are passed through An electric arc which disassociates and ionizes the gases. Then the atomic components recombine, producing a tremendous amount of Energy. In fact, the plasma core temperatures are typically greater than 10,000°C, Yet the target part is kept cooler than 350°F. powder is injected into the plasma, melted and accelerated onto the part's surface.

Plasma spraying was initially developed to spray ceramics and is still the premier process for applying them. metals and plastics can also be sprayed with this technique. The particle velocities for plasma are higher than those of flame and arc spraying and result in coatings that are typically denser and have a finer as-sprayed surface roughness.

popular plasma spray materials (ceramics)

zirconium oxide Primarily used for thermal barrier coatings. Recommended for combustion applications such as turbine combustion liners and airfoils, diesel engine pistons, valves, cylinder heads and coatings for casting molds and troughs. Abrasive wear resistant up to approx. 900°C (1650°F).

Aluminum oxide
Good resistance to abrasive wear, sliding wear, friction and oxidation up to approx. 1100°C (2040°F). Coatings are particularly suitable for applications in the textile or synthetic fiber manufacturing industries, where surface resistance is required on parts used for the guiding and handling of thread. can be used in many environments including most acids and alkalis.

Chrome oxide
Dense, corrosion resistant coatings used on pump seal areas, grounds, rolls and wear rings. Recommended for resistance to wear by abrasive grains, hard surfaces, particle erosion and cavitation all at temperatures below 540°C (1000°F). Coatings are insoluble in acids, alkalis and alcohol.

titanium oxide
Produces hard coatings with excellent resistance to abrasion, wear, heat and corrosion. Applications include dry cell battery core mandrels and drum doctor blades.