Influence of tool electrode feed rate in the electrochemical discharge drilling of a glass substrate

ABSTRACT

The tool electrode feed rate (TEFR) is a parameter of vital importance for velocity-feed electrochemical discharge drilling (ECDD). The tool electrode will hit the workpiece and may even cause to crack if higher TEFR is used, while a lower TEFR will curtail the material etch rate. Hence, a comprehensive experimental study into the TEFR effects on the ECDD performance is presented. The top and bottom sizes of micro-holes, eccentricity, circularity, heat-affected zone, and tool electrode wear are the important features considered in this experimental work. Cylindrical-shaped tungsten carbide tool electrodes with 70 μm and 300 μm sizes were utilized. The TEFR in the range of 1–9 μm s⁻¹ were selected. The stable and uniform EC discharges were observed for the TEFR < 5 μm s⁻¹. The minimal hole size and HAZ were obtained for the TEFR in the range of 3–4 μm s⁻¹. The eccentricity and circularity of micro-holes were found to be lower for the TEFR < 5 μm s⁻¹. Higher tool wear was noticed for the TEFR < 2 μm s⁻¹. Based on the overall experimental evaluation, TEFR in the range of 3–4 μm s⁻¹ is recommended.

KEYWORDS:

• ECM
• ECDM
• tool-electrodes
• feed -rate
• tool-wear
• circularity
• eccentricity
• heat-affected-zone

Acknowledgments

The authors appreciate the financial funding provided by the Ministry of Human Resources and Development (MHRD) as well as the Department of Scientific and Industrial Research (DSIR) (Grant: DSIR/PACE/TDD-IMPRINT/7510). Present work has been conducted as a part of MHRD, Govt. of India funded IMPRINT Project (Grant code: 10007457). J Arab is supported by the Inspire fellowship (Grant number: DST/INSPIRE fellowship/2017/IF160295) of the Department of Science and Technology (DST).

Additional information

Funding

This work was supported by the Department of Science and Technology, Ministry of Science and Technology [DST/INSPIRE fellowship/2017/IF160295]; Department of Scientific and Industrial Research, Ministry of Science and Technology [DSIR/PACE/TDD-IMPRINT/7510]; Ministry of Human Resource Development [10007457].