Effect of system parameters on the size distributions of hollow nickel microspheres produced by an ultrasound-aided electrical discharge machining process

- Hollow nickel microspheres were produced by ultrasound-aided electric discharge machining method.
- EDM machine used kerosene as dielectric medium, nickel strips as electrodes at 40 kHz ultrasounds.
- Short pulse widths, low voltages, and low currents favored formation of smaller microspheres.