Experimental investigations on overhead machining of magnesium alloy using MX–ND–EDM

This research article is an experimentally investigated for the machinability of Magnesium Alloy (AZ80) using design of experiment (DOE) technique employed to analyze the impact of three key input parameters, pulse-on-time, voltage, and discharge current on machining performance, and the experiment was performed using an in-house designed and developed, MX–ND–EDM was used with an overhead tool position as a new machining path for difficultto-access areas and better performance of the process. The objective was to enhance the MRR and minimize the TWR (Tool Wear Rate) under overhead machining conditions. Experimental results revealed that voltage had the least influence, while pulse-on-time showed a moderate effect on the performance measures. The optimized parameter combination: pulse-on-time 40 µs, discharge current 10 A, voltage 50 V, achieved maximum MRR (6.216 mm3/min) and at pulse-on-time 20 µs, discharge current 10 A, voltage 40 V, achieved minimum TWR (1.856 mm3/min), SEM analysis of the machined surface revealed microcracks, debris deposition, and craters. These findings provide valuable insights into the performance enhancement of MX–ND–EDM using the proposed overhead machining methodology.