TOPSIS on High Aspect Ratio Electric Discharge Machining (EDM) of Ti-6Al-4V using 300 μm brass rotary tube electrodes

In the present scenario, Electric Discharge Drilling (EDD) is one of the most versatile and globally accepted modern manufacturing systems for drilling small holes in electrically conductive materials which owns high hardness, high corrosion resistant and high melting point (such as Tantalum, Titanium and Inconel alloys). In this work, overcut (OC), radial error (RE) and material removal rate (MRR) of the machined hole were analyzed when high aspect ratio electrical discharge drilling of Ti-6Al-4V using 300 mu m brass rotary tube electrodes. An experimental design was carried out using an L27 Taguchi's orthogonal array using current, capacitance, on-time and off-time. From TOPSIS analysis, the ideal solutions found are current (4 A), capacitance (50 nF), on-time (6 mu s) and off-time (7 mu s). Further, the SEM micro analysis was enabled to assess and improve the magnitude of the results. (C) 2018 Elsevier Ltd. All rights reserved.