Experimental examination of the machining characteristics of Nimonic 80-A alloy on wire EDM

Abstract

Nimonic 80-A alloys are very hard alloys with high-temperature strength having an extensive application in the aerospace industry. Wire Electric Discharge Machining (WEDM) is one of the finest non -conventional machining processes, which due to the material removal taking place using spark erosion with Wire EDM, makes it very easy to machine hard alloys and composites. The accuracy of machining them makes it one of the most advanced non-traditional processes. Kerf width is an important output response during machining on WEDM. The experimental investigation is done to find the optimum machining parameters to minimize the kerf width. The experimental investigation was done using the Taguchi analysis considering input factors peak current, gap voltage, and pulse-on time at three levels for machining on WEDM. Taguchi L27 orthogonal array was applied to generate the required experiments to be performed on WEDM. The output response data kerf width obtained is analyzed using signal-to-noise (S/N) ratio values generated by the Taguchi design methodology. The three main input parameters like peak current (20-80A), gap voltage (30–60 V), and pulse-on time (20–70 μs) are considered within this range. The single response optimization is done of the experimental kerf width data obtained for 27 different settings of input parameters of WEDM. The influence of each of the variables on kerf width is interpreted using the S/N ratio graphs, finding the most appropriate settings to minimize the kerf width. The results were obtained with a specific range of parameters that can be analyzed further with other optimization models, to get a wider range of optimum parameter values. The research on optimizing the output response kerf width for Nimonic 80-A alloy during machining on WEDM has not been reported much in the literature. This new optimized machining data would provide better scope to machine Nimonic 80- A alloy for minimizing the kerf width.