Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
권호 표지

Improvement of Electrical Discharge Drilling

방전드릴링의 가공특성 향상

  • Song, Ki-Young (School of Mechanical and Aerospace Engineering, Seoul National Univ.) ;
  • Chung, Do-Kwan (School of Mechanical and Aerospace Engineering, Seoul National Univ.) ;
  • Park, Min-Soo (Department of Product Design and Manufacturing Engineering, Seoul National Univ. of Technology) ;
  • Chu, Chong-Nam (School of Mechanical and Aerospace Engineering, Seoul National Univ.)
  • 송기영 (서울대학교 기계항공공학부) ;
  • 정도관 (서울대학교 기계항공공학부) ;
  • 박민수 (서울산업대학교 제품설계금형공학과) ;
  • 주종남 (서울대학교 기계항공공학부)
  • Received : 2009.12.30
  • Accepted : 2010.08.03
  • Published : 2010.10.01
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Abstract

Electrical discharge drilling (ED-drilling) is a widespread machining method used to bore small holes with a high aspect ratio. This paper presents additional methods by which ED-drilling can improve machining speed, tool wear, and machined surface quality. Firstly, for high machining speed, and low tool wear, a new-type electrode that was ground on one side or both sides of the cylindrical electrodes was suggested to expel debris. The debris which is generated during the machining process can cause sludge deposition and secondary discharge problems: major reasons to decrease machining speed. This new-type electrode also reduced tool wear that was due to the decrease of unstable discharge in a machining gap by helping to expel waste water and debris from the gap. Secondly, to improve the machined surface roughness, an electrolyzation process was included after drilling. This process made the machined surface smooth by means of an electrochemical reaction between an electrode and a workpiece. In this study, the machining speed, electrode wear, and surface roughness were improved by the newtype electrode and the electrolytic process.

Keywords

References

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