Investigation of the effects of magnetic field on near-dry electrical discharge machining performance

The stability of electrical discharge machining process would be improved by better expelling debris from machining gap. In this investigation, a rotational external magnetic field was applied around machining gap of near-dry electrical discharge machining process to make a new hybrid method for machining of stiff and high-strength parts. The Taguchi method of design of experiments was employed to study the effects of applying magnetic field in near-dry electrical discharge machining process. The experimental results showed that in magnetic field-assisted near-dry electrical discharge machining, material removal rate is more and surface roughness is less than in near-dry electrical discharge machining process without magnetic field, but tool wear rate is a little more. Also, the optical micrographs of the surfaces machined indicated better surface integrity resulted by magnetic field-assisted near-dry electrical discharge machining as compared to near-dry electrical discharge machining process without magnetic field.