In electrical discharge machining (EDM), material is removed by a series of electrical sparks that develops a temperature in the range 8 000 C-12 000 C between the electrode and the workpiece. Due to the high temperature of the sparks, the workpiece is melted and vaporized. At the same time, the electrode material is also eroded by melting and vaporization. This erosion of the electrode is termed as electrode wear (EW). The EW process is similar to the material removal mechanism as the electrode and the workpiece are considered as a set of electrodes in EDM. Due to EW, electrodes lose their dimensions resulting in inaccuracy of the cavity formed by EDM. This paper reports on the study of the effect of electrode cooling during the EDM of titanium alloy (Ti-6Al-4V). Investigation on the effect of electrode cooling on electrode wear was carried out. Current, pulse on-time, pause off-time, and gap voltage were considered as the machining parameters while EW is the response. Analysis of the influence of electrode cooling on the response has been carried out, and it was possible to reduce EW by 27% using this method.
In electrical discharge machining (EDM), material is removed by a series of electrical discharge between the electrode (tool) and the workpiece that develops a temperature of about 8,0000C to 12,0000C. Due to high temperature of the sparks, work material is melted and vapourized, at the same time the electrode material is also eroded by melting and vapourization. Electrodes wear (EW) process is quite similar to the material removal mechanism as the electrode and the workpiece are considered as a set of electrode in EDM. In the present study effort has been made to reduce EW by cooling, using liquid nitrogen during the EDM of titanium alloy. Investigation on the effect of cooling on electrode wear (EW), material removal rate (MRR) and surface roughness (Ra) of the workpiece was carried out. Current (I), pulse on-time (ton), pause off-time (toff) and voltage (v) were considered as the machining parameters. Design of experiment (DOE) was used to design the experimental works. Cooling of electrode by this technique reduced the melting and vapourization of electrode material and enhances electrode life. It was possible to reduce EW up to 27% by applying this technique while MRR and Ra were improved by 18% and 8% respectively.
Electrical discharge machining (EDM) process is a manufacturing method for shaping hard metals and formation of deep and complex shaped hole by spark erosion in electrical conductive materials such as metals, metallic alloys, ceramics etc. EDM process is achieved by a series of recurring electrical discharges between the electrode and workpiece in the presence of dielectric fluid. EDM unique feature of using thermal energy to machine conductive materials irrespective of material hardness has been its major advantage in the manufacture of aerospace, surgical, mould, die, automotive and as well as sport components. The effectiveness of EDM process depends among other factors on the thermal properties of the electrode material. The objective of this study is to study the influence of electrode cooling on recast layers and micro crack in EDM of titanium. The machining parameters investigated in the present study are current intensity (I), pulse on-time (Ton), pulse off-time (Toff) and gap voltage (V), which are of great interest for EDM researchers. The copper electrode is used to EDM titanium workpiece at room temperature and at sub-zero temperature using liquid nitrogen. The influence of cooling of copper electrode on recast layers and micro crack on titanium were investigated using scanning electron microscope (SEM) and has been reported in this study.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.