With plasma spraying all sprayable materials can be used.
The plasma arises by a strong arc which is drawn between a positive anode and a negative cathode. This arc ionises a process gas in a plasma status. The arc is held in the plasma pistol between the axial electrode and a water cooled nozzle. As the plasma gas has been heated by the arc, it expands and quickens it through a specially formed nozzle.
The temperature in the arc zone approaches 20,000°C. The temperature in the plasma jet is still 10,000°C at a few centimetres from the nozzle exit.
As the material in powder form is injected into the plasma flame, it melts and is projected on to the work piece. The particle velocity may go up to 450m/s. Due to the extremely high temperature, plasma spraying is particularly suitable to spray on materials with a high melting point, such as ceramics.
- Chrome oxide
- Aluminium titan oxide
- Zirconium oxide
- Aluminium oxide
- YsZ (yttria stabilized zirconium)