Investigation on Micro Electric Discharge Machining of Wire Arc Additive Manufactured Inconel 625

Abstract:

This study investigates the optimization of machining parameters for fabricating micro-holes in Wire Arc Additive Manufactured (WAAM) Inconel 625 using Micro Electric Discharge Machining (Micro EDM). An experimental design based on the Taguchi L9 orthogonal array was employed, focusing on the effects of input current (Ip), pulse-on time (Ton), and pulse-off time (Toff). Using copper electrodes, 800 µm diameter micro-holes were machined, and responses such as Material Removal Rate (MRR), Tool Wear Rate (TWR), and dimensional accuracy (DA) were analyzed. Signal-to-Noise (S/N) ratio analysis was used to determine optimal machining conditions, achieving maximum MRR, minimum TWR, and enhanced DA. The results revealed that the optimal parameters for achieving these objectives were Ip = 2 A, Ton = 5 µs, and Toff = 9 µs. This research highlights the effectiveness of the Taguchi method and S/N analysis in enhancing machining performance for WAAM Inconel 625, contributing to improved precision and efficiency in manufacturing processes.

• Periodical: Engineering Headway (Volume 41)
• Pages: 13-24
• DOI: https://doi.org/10.4028/p-At8sQh
• Online since: July 2026
• Authors: A. Ragul*, J. Pradeep Kumar, Somasundara Vinoth
• Keywords: Inconel 625, Micro EDM, Micro-Holes, Optimisation

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