Gases fed through the plasma gun and turned into plasma by the arc. The primary gas, usually argon or nitrogen, sets the flow and velocity and stabilizes the arc. A secondary gas, typically hydrogen or helium, raises arc voltage and the heat content and conductivity of the jet, so it controls how well particles melt. Flows are set in SLPM or SCFH and are among the most closely controlled parameters.
Ceramic's not melting, bump the hydrogen from 8 to 10 on the plasma gas and watch the voltage.
Also heard as
- primary gas
- secondary gas
- arc gas
Related terms
Plasma spray
Spraying powder through an electric arc plasma jet hot enough to melt ceramics and refractory metals.
Gun voltage
The arc voltage of a plasma gun, watched as a live indicator of gas mix, power and hardware wear.
SLPM
Standard liters per minute: gas flow corrected to standard temperature and pressure.
Running hot
Booth talk for parameters that are overheating the particles or part; running cold is the opposite.