Microparticle flow generation by a ferroelectric plasma source

The paper presents the experimental results of the investigation of microparticle emission from a Ba-Ti-based ferroelectric sample subjected to a driving pulse with a slow rise time and a fast fall time. It was found that the formation of incomplete discharges on the surface of the ferroelectric is accompanied by the emission of an intense positively charged rnicroparticle flow. This microparticle flow (density, velocity distribution, momentum and average microparticle charge) was studied using electrical and optical diagnostics at different distances from the front surface of the ferroelectric sample and at several time delays with respect to the fast fall of the driving pulse. It was shown that microparticles are positively charged at about 6 x 10(-15) C; they have an average size of about 5 mu m, a density of about 7 x 10(4) cm(-2) and an average velocity of about 6 x 10(3) cm s(-2). The mechanism of the formation of these microparticles and the application of microparticle flows as a propellant for a small thruster are discussed.