Todays, since using metallic nanoparticles has been developed in various industries, achieving new methods to produce them is considered as an important issue. Comparing to other nanoparticle production methods, the dielectric discharge process has been emphasized due to its low cost and environmental compatibility. In this study, the ultrasonic-assisted electrical discharge process is designed and manufactured in order to produce copper nanoparticles in three different di-electric medium: pure di-ionized water, di-ionized water solution and polyethylene glycol, and kerosene. The different machining parameters effect, as current intensity, pulse on/off time, and the ultrasonic vibrations on the produced particle size, material removal rate, suspensive particle stability in the fluid, and the particle abundance percentage is investigated. Characterizing the produced nanoparticles is done by different methods. Determining the purity of nanoparticles, percentage of abundance and the average particle size in the dielectric fluid and the produced particle size has been done by applying Energy Dispersive Analysis by X-ray (EDAX), Dynamic Light Scattering (DLS) and Field Emission Scanning Electronic Microscope (FESEM) image, respectively. Based on the results, the produced nanoparticles purity and the average particle size were more than 95% and less than 100 nm, respectively. Their stability and sedimentation time were significantly increased. Moreover, the particle size was almost uniformly distributed. Keywords: Nano-particles, Electrical discharge, Ultrasonic vibration, Characterization
