0
Research Papers

A Model of Micro Electro-Discharge Machining Plasma Discharge in Deionized Water

[+] Author and Article Information
Soham S. Mujumdar

Graduate Student
Department of Mechanical Science
and Engineering,
University of Illinois at Urbana-Champaign,
Champaign, IL 61801
e-mail: mujumda2@illinois.edu

Davide Curreli

Assistant Professor
Department of Nuclear, Plasma
and Radiological Engineering,
University of Illinois at Urbana-Champaign,
Champaign, IL 61801
e-mail: dcurreli@illinois.edu

Shiv G. Kapoor

Professor
Department of Mechanical Science
and Engineering,
University of Illinois at Urbana-Champaign,
Champaign, IL 61801
e-mail: sgkapoor@illinois.edu

David Ruzic

Professor
Center for Plasma-Material Interactions,
Department of Nuclear, Plasma
and Radiological Engineering,
University of Illinois at Urbana-Champaign,
Champaign, IL 61801
e-mail: druzic@illinois.edu

1Corresponding author.

Contributed by the Manufacturing Engineering Division of ASME for publication in the JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING. Manuscript received August 2, 2013; final manuscript received December 11, 2013; published online March 26, 2014. Assoc. Editor: Y.B. Guo.

J. Manuf. Sci. Eng 136(3), 031011 (Mar 26, 2014) (12 pages) Paper No: MANU-13-1300; doi: 10.1115/1.4026298 History: Received August 02, 2013; Revised December 11, 2013

For successful commercial adaptation of the μ-EDM (micro electro-discharge machining) process, there is a need to increase the process efficiency by understanding the process mechanism. This paper presents a model of the plasma discharge phase of a single discharge μ-EDM event in deionized water. The plasma discharge is modeled using global model approach in which the plasma is assumed to be spatially uniform, and equations of mass and energy conservation are solved simultaneously along with the dynamics of the plasma bubble growth. Given the input discharge voltage, current and the discharge gap, complete temporal description of the μ-EDM plasma during the discharge time is obtained in terms of the composition of the plasma, temperature of electrons and other species, radius of the plasma bubble and the plasma pressure. For input electric field in the range of 10–2000 MV/m and discharge gap in the range of 0.5–20 μm, time-averaged electron density of 3.88×1024m-3-30.33×1024m-3 and time-averaged electron temperature of 11,013–29,864 K are predicted. Experimental conditions are simulated and validated against the spectroscopic data from the literature. The output from this model can be used to obtain the amount of heat flux transferred to the electrodes during the μ-EDM process.

FIGURES IN THIS ARTICLE
<>
Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Schematic of a single discharge of μ-EDM process showing three main phases: (a) Dielectric breakdown phase, (b) discharge phase, and (c) postdischarge phase (1: Electrodes, 2: Dielectric, 3: Vapor bubble, 4: Plasma discharge column, 5: Melt-pool, 6: Debris, 7: Bubbles, 8: Crater)

Grahic Jump Location
Fig. 2

Global model of μ-EDM process

Grahic Jump Location
Fig. 3

Plot of temperature-dependent reaction rates of a few significant reactions in H2O plasma (listed in Table 6 in the Appendix)

Grahic Jump Location
Fig. 4

Energy flow diagram of μ-EDM plasma showing interaction between electrons, ions, and neutral species in an expanding plasma bubble

Grahic Jump Location
Fig. 5

Evolution of plasma characteristics

Grahic Jump Location
Fig. 6

Electric field (E)–Gap (L) domain of the μ-EDM plasma model (square represents point is [E, L] domain where discharge was successfully simulated, and circle represents failure of the model in obtaining plasma evolution at point [E, L])

Grahic Jump Location
Fig. 7

Paschen like curve for H2O using μ-EDM plasma model (square represents point is [V, pL] domain where discharge was successfully simulated, and circle represents failure of the model in obtaining plasma evolution at point [V, pL])

Grahic Jump Location
Fig. 8

Effect of applied electric field and discharge gap on the time-averaged plasma characteristics, namely, total plasma density, plasma temperature, electron density, plasma pressure, final plasma radius, and heat flux to workpiece

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In