Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Control of Taper Shape in Micro-Hole Machining by Micro-EDM

방전 가공을 이용한 미세 구멍 가공 시 발생하는 테이퍼 형상의 제어

  • 김동준 (서울대학교 대학원 기계항공공학부) ;
  • 이상민 (서울대학교 대학원 기계항공공학부) ;
  • 이영수 (서울대학교 정밀기계설계공동연구소) ;
  • 주종남 (서울대학교 기계항공공학부)
  • Published : 2005.04.01
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Abstract

When a micro hole is machined by EDM with a cylindrical electrode, the hole diameter is different at the inlet and the outlet of the micro hole. The taper shape of the micro hole is caused by not only wear of the electrode but the eroded particles. The eroded particles cause secondary discharge during machining the micro hole. As a result, the diameter of the inlet becomes larger than that of the outlet. In this paper, a new method is proposed to reduce the difference in diameter between the inlet and the outlet of the hole. Observed was that the feed depth and machining time affect the formation of taper shape On this experimental basis, ultrasonic vibration was applied to reduce machining time, and capacitance was changed during machining to use the difference in discharging energy of different capacitances. Using the proposed method, a straight micro-hole was fabricated.

Keywords

References

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