Effect of powder loading on the excitation temperature of a plasma jet in DC thermal plasma spray torch

A DC non-transferred mode plasma spray torch was fabricated for plasma spheroidization. The effect of powder-carrier gas and powder loading on the temperature of the plasma jet generated by the torch has been studied. The experiment was done at different input power levels; the temperature of the jet was within 5000–7000 K argon was used as plasma gas and powder-carrier gas. Nickel powder particles in the size range from 40 to 100 μm were processed. The temperature of the jet was estimated after flowing powder-carrier gas only into the plasma jet and with powder-carrier gas feeding powder into the flame. On introduction of powder-carrier gas and powder loading the temperature of the jet was found to decrease appreciably down to 11%. The temperature of the plasma jet was estimated using the Atomic Boltzmann plot method.