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Journal of Materials Engineering and Performance

, Volume 23, Issue 4, pp 1392–1401 | Cite as

Experimental Investigation of Wire Electrical Discharge Machining of NdFeB Permanent Magnets with an RC-Type Machine

  • Jeremy Greer
  • Andrew J. Petruska
  • Arthur W. Mahoney
  • Manikantan Nambi
  • Eberhard Bamberg
  • Jake J. Abbott
Article
  • 290 Downloads

Abstract

This paper focuses on wire electrical discharge machining (WEDM) of devices made from commercially available sintered neodymium-iron-boron (NdFeB) rare-earth magnets that have been magnetized before machining. We conduct an experimental study to quantify the effects of the voltage and capacitance of an RC-type WEDM machine, as well as the magnet polarity, on slicing rate, mean kerf, and variation in kerf. We find that voltage and capacitance affect slicing rate, that voltage affects mean kerf, that no parameters tested affect the variation in kerf, and that the polarity of the magnet being machined does not affect the machining process. Linear regression is used to fit simple predictive models to the data with good agreement. Further analysis is performed to characterize the loss in permanent magnetization on the surface of the magnet due to heating during the machining process, and it is found that the outer layer of approximately 35 μm in depth is demagnetized when using the highest voltage and capacitance values tested.

Keywords

demagnetization EDM kerf magnetization slicing rate 

Notes

Acknowledgment

This material is based upon work supported by the National Science Foundation under Grant Nos. 0952718 and 0654414.

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Copyright information

© ASM International 2013

Authors and Affiliations

  • Jeremy Greer
    • 1
  • Andrew J. Petruska
    • 1
  • Arthur W. Mahoney
    • 2
  • Manikantan Nambi
    • 1
  • Eberhard Bamberg
    • 3
  • Jake J. Abbott
    • 1
  1. 1.Department of Mechanical EngineeringUniversity of UtahSalt Lake CityUSA
  2. 2.School of ComputingUniversity of UtahSalt Lake CityUSA
  3. 3.Viteris TechnologiesSalt Lake CityUSA

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