ULTRASONIC EFFECT ON ELECTRIC SPARK FORMING AND DEVELOPMENT IN ELECTROACOUSTIC SPRAYING

Abstract

Introduction. The electroacoustic application of wear-resistance coatings is studied. The work objective is to obtain a mathematical model of the ultrasonic effect on the formation and development of an electric spark occurring in the process of the electroacoustic sputtering.Materials and Methods. The effect of ultrasonic vibrations on the processes occurring during the formation and development of a spark discharge is analyzed; the equations of continuity, energy motion and transfer, with the ultrasonic field contribution are considered. Factors affecting the thermal conductivity and electrical conductivity of strongly ionized gas are studied. Research Results. When obtaining the model, it was assumed that the heat removal from the channel is carried out by a “clear emitter”. Then, for the channel region, a self-similar solution is made: pressure, temperature and density are constant over the cross-section, and velocity is proportional to the radius. A mathematical model that describes the processes occurring in the spark channel with the ultrasonic field energy effect is obtained.Discussion and Conclusions. On the basis of the developed model, it is specified that under the ultrasonic radiation effect, the radius and temperature of the spark channel increase, and conditions of the double ionization under high ultrasonic energy are created.

Keywords

• electroacoustic spraying
• hardening
• hardening coatings
• highly concentrated energy flows
• ultrasound
• electric spark
• mathematical model
• conductive channel
• thermodynamics
• ionization