Sustainable developments in near-dry electrical discharge machining process using sunflower oil-mist dielectric fluid.

Abstract

In this study, a near-dry electrical discharge machining (NDEDM) process has been conducted using compressed air mixed with a low quantity of biodegradable refined sunflower oil (called oil-mist) to investigate the machining characteristics. The Box-Behnken method looks at how oil flow rate (OR), air pressure (AR), spark current (SC), and pulse width (PW) affect gas emission concentration (GEC), material removal rate (MRR), and surface roughness (SR). The TOPSIS (The Technique for Order of Preference by Similarity to the Ideal Solution) technique estimates the parameter optimal set for the best machining characteristics. The optimal machining parameters have been used to examine the microstructure of the machined surfaces using a scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) analysis. The 0.981mg/min of GEC, 55.145mg/min of MRR, and 2.43µm of surface roughness have been attained by the 14ml/min flow rate, 7bar of air pressure, 10 A spark current, and 48µs pulse duration of the sun-flower oil-mist NDEDM process.