Generation and Characterization of Copper Nanoparticles Using Micro-Electrical Discharge Machining

The present article describes the generation of copper nanoparticles in the base fluid using developed micro-electrical discharge machining (micro-EDM) process. Micro-EDM was performed with various operating parameters such as voltage, current, pulse width and duty factor. To prevent agglomeration and coagulation of nanoparticles, polyvinyl alcohol (PVA) and polyethylene glycol (PEG) are used as stabilizers. The characterization of the generated copper nanofluid is done by energy dispersive analysis by X-rays, selected area electron diffraction pattern and transmission electron microscope followed by the study of thermal conductivity and viscosity of nanofluid using KD-2 pro device and falling ball type viscometer. The viscosity measurement enables to determine the dispersion stability of copper nanofluids. The experimental results show that the mean size of generated spherical copper nanoparticles is found to be less than 10 nm. It was observed that the thermal conductivity of copper–de-ionized (DI) water, copper–DI water with PVA and PEG nanofluids are 6%, 14% and 15% are higher than that of pure DI water. Also, it was found that there is a reduction of 96% and 99.9% in the sedimentation velocity of copper nanoparticles in copper–DI water with PVA and PEG nanofluid when compared to copper–DI water nanofluid resulting in excellent dispersion stability of the nanoparticles in copper–DI water with PEG nanofluid rather than PVA nanofluid.