Authors: Dave (Dae-Wook) Kim, Xiaolin Chen, Phil Allen
Addresses: School of Engineering and Computer Science, Washington State University, Vancouver, WA 98686, USA. ' School of Engineering and Computer Science, Washington State University, Vancouver, WA 98686, USA. ' The Boeing Co., Seattle, WA 98124, USA
Abstract: In this study, the material removal mechanism for micro-EDM of molybdenum was investigated numerically and experimentally using both single and multiple spark investigations. Single-spark material removal was analysed using a thermo-numerical model which simulated a single spark discharge process and was compared with single-spark experiments. Good correlation between the numerical and experimental data was observed. Multiple-spark material removal was investigated through the creation of apertures using an experimental design in which the input voltage and pulse duration were varied. The material removal rate of molybdenum increases with increasing input voltage and decreasing pulse duration, while the tool wear increases as both input parameters increase. Material removal and debris formation mechanisms are examined as well as the effect of machining parameters on process outputs and aperture quality. A comparably shorter pulse duration is appropriate to produce micro-size molybdenum apertures with a higher removal rate and a lower surface defect such as debris.
Keywords: micro-EDM; molybdenum aperture; numerical modelling; material removal rate; MRR; tool wear; micron-size hole quality; electro-discharge machining; electrical discharge machining; drilling; experimental design; debris formation; aperture quality; surface defects; pulse duration.
International Journal of Machining and Machinability of Materials, 2010 Vol.7 No.3/4, pp.161 - 175
Published online: 07 May 2010 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article