Effects of variable magnetic field assisted EDM on MRR and surface integrity of AZ80 magnesium

Abstract

ABSTRACT Magnetic field-assisted electrical discharge machining (MFEDM) is [non-conventional method] employed to optimize and improve output parameters in electrical discharge machining (EDM) and has recently been of great interest to researchers. In EDM, a magnetic field is created by the movement of electrons in the plasma channel. It can be inferred from this theory that a rise in the magnetic field strength raises the plasma channel density and energy concentration. The present study aims to explore the effects of a variable magnetic field on the material removal rate (MRR) and surface integrity in MFEDM, comparing the variable magnetic field-assisted EDM to constant magnetic field-assisted EDM and conventional EDM. The AZ80 magnesium alloy was used for the workpiece which, due to its unique properties, has been widely used in many industries in recent years. Moreover, magnesium is paramagnetic and can yield different results in MFEDM. It was found that the external magnetic field increased the MRR by 58% and reduced the surface roughness in magnesium AZ80. In addition, the variable magnetic field outperformed the constant one in improving MRR and surface roughness. Also, the results showed that the auxiliary magnetic field is more effective on the surface roughness of ferromagnetic metals than paramagnetic metals.