Localized Electro-chemical Micro Drilling Using Ultra Short Pulses

초단펄스 전해 국부화를 이용한 미세구멍 가공

  • 안세현 (서울대학교 기계항공공학부) ;
  • 류시형 (서울대학교 공학연구소) ;
  • 최덕기 (강릉대학교 정밀기계공학과) ;
  • 주종남 (서울대학교 기계항공공학부)
  • Published : 2003.08.01

Abstract

By the localization of electro-chemical dissolution region, we succeeded in a few micrometer size hole drilling on stainless steel with the radial machining gap of about 1 ${\mu}{\textrm}{m}$. Tens of nanosecond duration voltage pulses were applied between WC micro-shaft and stainless steel in the 0.1 M $H_2SO_4$ solution. Pt balance electrode was used to drill the high aspect ratio micro-hole without generation of Cr oxide layer on the machined surface. The effects of applied voltage, pulse duration, and pulse period on localization distance were investigated according to machining time. We suggested the taper reduction technique especially brought up on blind-hole machining. High quality micro-holes with 8 ${\mu}m$ diameter with 20 ${\mu}m$ depth and 12 ${\mu}m$ diameter with 100 ${\mu}m$ depth were drilled on 304 stainless steel foil. The various hole shapes were also produced including stepped holes and taper free holes.

Keywords

References

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