Effect of wire material and discharge energy on productivity and surface integrity of WEDM-processed Inconel 718

ABSTRACT

The current work aims to study the influence of discharge energy and debris accumulation on wire break failure and surface integrity aspects like surface roughness, subsurface hardness, and geometrical errors during the wire EDM of Inconel 718. The responses considered for analysing the geometrical accuracies are flatness error, roundness error and cylindricity error. Four different wire electrodes were considered for the study based on the wire strength and coatings, namely hard zinc coated brass, half-hard zinc coated brass, hard uncoated brass, and half-hard uncoated brass wire electrodes. The geometric accuracy of the machined parts is closely related to the choice of wire electrode. High-tensile strength hard wires were observed to machine the surfaces with maximum accuracy. Also, the zinc coated wires were observed to cut faster compared to the uncoated wire electrodes. The study revealed that there exists a strong influence of discharge energy on the surface integrity of wire electric discharge machined surface. The zinc and copper elemental contamination was minimal for uncoated wire electrodes at lowest discharge energy mode. Wire wear phenomena was analysed for both coated and uncoated wires. Discharge energy had a significant impact on the electrode wear of coated and uncoated wire electrode.

KEYWORDS:

• WEDM
• discharge energy
• geometric accuracy
• surface integrity
• wire wear
• coated electrode
• Inconel 718

Acknowledgments

The authors would like to thank the central instrumentation facility (CIF), IIT Palakkad, for providing the test facility and equipment.

Data availability statement

All the data relevant for the study are given in the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.