الفهرس | Only 14 pages are availabe for public view |
Abstract The present investigation presents a study of sinking electric discharge machining assisted by magnetic field process with different features. In this work, a copper and graphite electrodes are proposed as electrode tools in electric discharge machining assisted by magnetic field process for high performance alloy, armoured steel (500HV). The working parameters, namely, peak current, magnetic flux density, duty factor and dielectric fluid pressure are investigated to study performance criteria, i.e., metal removal rate (MRR), tool wear rate (TWR) and surface roughness (Ra, Rz). An experimental study is presented through performing series of designed experiments. For this purpose, a designed and fabricated test rig was used. The experimental results are statistically analyzed and mathematically modeled through response surface methodology (RSM). The results reveal that using EDM assisted by magnetic field through copper and graphite electrodes for armoured steel (500HV) is an economical method. It saves the expenses of the EDM process and adds a new controlling parameter, magnetic flux density. The results reveal that MRR, TWR and surface roughness (Ra, Rz) are significantly improved with the increase of magnetic flux density when using both electrodes. The dielectric fluid pressure has a moderate effect when machining by EDM assisted by magnetic field for the two electrodes. Also, the results revealed that EDM assisted by magnetic field could facilitate the expulsion of machining debris to reduce the probability of abnormal electrical discharge, so the surface cracks were relatively less on the machined surface. |