Magnetic field assisted micro electro-discharge machining

This paper studies the feasibility of application of a magnetic field to obtain higher aspect ratio micro holes on hardened tool steel using the micro electro-discharge machining (micro EDM) process. The magnetic field has been introduced to improve debris circulation. Implementing magnetic force perpendicular to the electrode's rotational force produces a resultant force that is efficient in transporting debris out of the hole during machining. With the magnetic field assisted micro EDM process a hole depth of 1177 mum is achieved in 360 min in tool steel. This is 26% higher when compared with the conventional micro EDM process under similar working conditions. No significant difference is noticed in the side wall surface roughness values in the two cases.