Pulsed Laminar Arc Jet Associated with Phase Injection of Suspension for Coating Elaboration Available to Purchase

This paper presents a new approach to overcome arc plasma instabilities in suspension plasma spraying. The method employs a dc plasma torch with a large cathode cavity. This design modification reduces the Helmholtz frequency of the torch, resulting in a new oscillation mode with a very regular voltage signal. In the experiments, droplets of a TiO₂ suspension are injected into the pulsed laminar arc jet in synch with the Helmholtz resonant frequency. Interactions between the plasma and droplets are observed by time-resolved imagine techniques and are discussed.