Optimization of micro-WEDG parameters 
for high-precision machining of Nimonic-C263

Nimonic-C263, known for its high density, durability, and corrosion resistance, poses significant challenges to conventional machining in terms of maintaining dimensional accuracy and surface quality. To address these issues, this study investigates the use of micro-wire electro-discharge grinding (m-WEDG), an advanced machining technique suited for fabricating precision micro-tools from hard-to-machine materials. The process parameters—spindle speed (SS), voltage (V), and capacitance (C)—were optimized to minimize surface roughness (Ra) and maximize material removal rate (MRR). A 400 µm micro-pin was fabricated from a 1 mm diameter Nimonic-C263 rod to evaluate machining performance. Using the Taguchi method, optimal conditions achieved an MRR of 0.20 mm³/min and a R a of 1.670 µm. Computational modeling was employed to analyze the parametric effects, confirming improvements in machining efficiency. Surface analysis via energy dispersive spectroscopy (EDS) revealed pyrolytic oxygen and carbon deposition, while field emission scanning electron microscopy (FESEM) showed minor surface waviness. This study provides a theoretical framework linking process parameters to machining performance, contributing to advancements in precision micro-manufacturing.