Spectroscopic and Electrical Diagnostic of the Plasma Jets Characteristic of a New Plasma Torch for LPPS or VLPPS

A plasma torch with a converging-diverging nozzle has been developed for low pressure plasma spraying. This study investigates the current-voltage characteristics of the plasma arc for argon and argon-hydrogen plasma gases and the effect of hydrogen volume percentage on the plasma jet. Emission spectroscopy is used to analyze the plasma spectra and electron temperatures in the center of the plasma jet are determined based on a Boltzmann distribution. The results show that an increase in input power considerably increases electron temperature and that gas composition has a significant effect on current-voltage characteristics. The impact of detection distance is also addressed.