Fabrication of micro-hole using novel Maglev EDM

Abstract

In the current scenario, micro-manufacturing through the electro-discharge machining (EDM) process is a prominent technique for achieving desired complex micro/nano-features of any product. The precision and accuracy of producing features are the prerequisites of micro-machining. The current work aims to check the feasibility of the novel Maglev EDM for fabricating micro-holes on a thin nickel sheet (thickness = 500 m). The study presents the viability of the newly developed system by comparing it with the conventional EDM process. A pure direct current power supply is assembled with a magnetic levitation-based gap monitoring mechanism to overcome the setbacks of conventional EDM. The novel setup utilizes the combined effect of the permanent electromagnet to diminish arcing and short-circuiting. The control parameters for the operation were 12 V open-circuit voltage and 2 A peak current while maintaining a duty factor of 95.564 percent. The measured discharge voltage and discharge current were 6.64 V and 900 mA, respectively. Tungsten rod (ø 650 m) and deionized water were used as a tool and a dielectric medium, respectively, for the experiment. Further, the machined micro-hole and micro-tool analysis have been carried out using high-resolution microscopy, scanning electron microscopy and energy dispersive spectroscopy reports. The newly developed Maglev EDM’s feasibility to produce micro-holes on conductive materials has been confirmed in the present work with an average material removal rate of 40 g/min.

Investigation of enhancing EDM machining performance of INCONEL alloy using composite electrodes

“…At lower magnification of 100X, the surface revealed the globules and uneven machined surface as depicted in figure 5(a). EDM, machining takes places by means of melting and vaporization, When the voltage was applied the material from the surface of the Inconel gets melted, owing to the incomplete flushing some of the melted materials redeposited over the machined surface which reduce the surface quality [49]. The uneven machined surface was formed because of uneven heat distribution, which occurs because of uneven tool wear.…”

Short review on the development of electrical discharge machine

“…Owing to EDM's practicality, the process has extended up to the micro-level, i.e., micro-EDM. EDM has become a valuable technique for producing micro features [3], in hard materials. The EDM process has tremendous advantages in that there is no barrier of hardness in machining [4], due to the thermal erosion of work material.…”

A comparative experimental study of different magnetic field intensities on electrical discharge turning of EN24 steel alloy

“…Sahoo et al 16 have checked that the feasibility of the novel Maglev EDM system for fabricating micro-holes on a 500 µm thin nickel sheet was assessed, and it was compared with conventional EDM. A direct current power supply integrated with a magnetic levitation-based gap monitoring mechanism was employed to reduce arcing and short-circuiting.…”