Air Plasma Spray (APS)
Atmospheric plasma spraying APS
Atmospheric Plasma Spray (APS) Systems are the most versatile and flexible thermal spray process due to its ability to spray a wide range of materials such as most metals, ceramics and alloys onto many different substrate materials such as plastics, glass, metals, ceramics and composite materials. Also, a broad range of powder particle sizes can be used. Benefits of APS include resistance against heat, oxidation and wear, corrosion protection, clearance control for abrasives and abradables, temperature management as well as electrical resistivity and conductivity. Thus APS can be used for a wide range of applications across industries.
Typical coatings
- Ceramics
- Carbides & Cermets
- Iron, Nickel & Cobalt based alloys
- Abradables
Main applications
- Wear resistance, Sliding, Abrasive, Erosion, etc
- Corrosion resistance
- Thermal barriers
- Combinations
In this line-of-sight process that is carried out in an open atmosphere, a high-powered jet of ionized argon and/or helium or hydrogen (plasma) melts ceramic powders and other high-temperature materials. The molten particles are then sprayed on a carefully cleaned and prepared surface.
Applications of APS
APS renders porous coatings and is only suitable for materials that tolerate brief exposure to atmospheric conditions
Used to spray hard facing materials and other build-up materials in less demanding applications, thus offering a more economical alternative to High Velocity Oxygen Fuel (HVOF) spraying
Mainly used to spray Thermal Barrier Coatings (TBC) on turbine components of any size
Also for application of chromium carbide hard-facing coatings for better fretting resistance on combustion parts
TBC coatings
APS TBC coatings require careful cleaning immediately before the application of the (metallic) bond coating and the ceramic TBC
TBC thickness can be selected between 200 and 1,000 microns or more
Standard TBC coatings are zirconium oxide with 8% yttrium oxide for phase stabilization
The density of the TBC coatings, which has to be optimized for durability, is selected by setting the process parameters