Journal of the Korean Society of Manufacturing Technology Engineers (한국생산제조학회지)

The Korean Society of Manufacturing Technology Engineers (한국생산제조학회)
권호 표지

Electrochemical Machining of Tungsten Carbide Microshaft

텅스텐 카바이드 미세축의 전해가공

  • 이강희 (동양미래대학 로봇자동화학부)
  • Received : 2010.04.02
  • Accepted : 2010.05.15
  • Published : 2010.06.15
Download PDF
⟨ Previous Next ⟩

Abstract

Tungsten carbide microshaft is used as micro punch, electrode of micro electro discharge machining, and micro tool because of its high hardness and rigidity. In this research, tungsten carbide microshaft was fabricated using electrochemical machining. $H_2SO_4$ solution was used as the electrolyte because it can dissolve tungsten carbide and cobalt simultaneously. Experimentally studied were the effects of electrolyte concentration, machining time, and machining voltage on material removal rate and the shape of the microshaft. To eliminate the effects of bubbles and metal corrosion layer on microshaft shape, the machining was performed below the electrolysis voltage. Three step electrochemical process was suggested to fabricate the straight tungsten carbide microshaft. As a result, a straight tungsten carbide microshaft of $30{\mu}m$ in diameter and $500{\mu}m$ in length was obtained through the proposed three step electrochemical process.

본 연구에서는 전해가공을 이용해서 직경이 균일한 텅스텐 카바이드 미세축을 제작하는 실험을 수행하였다. 전해가공을 통해 미세축으로 사용 가능한 형상을 얻기 위한 최적의 가공 조건에 대해 고찰하였다 이 과정에서 미세축의 형상에 영향을 주는 여러 인자들을 적절하게 조절하여 최적의 형상을 얻을 수 있었다. 그리고 가공된 미세축을 이용하여 적절한 조건으로 2차, 3차 가공을 수행하여 초미세축을 가공할 수 있음을 보였다. 그리하여 실험 결과 직경 $30{\mu}m$, 길이 $500{\mu}m$의 텅스텐 카바이드 미세축을 제작하였다.

Keywords

References

  1. Muller, E. W. and Tsong, T. T., 1969, Field ion microscopy, Elsevier, New York, USA.
  2. Fotino, M., 1993, "Tip sharpening by normal and reverse electrochemical etching," Rev. Sci. Instrum. Vol. 64, No. 1, pp. 159-167. https://doi.org/10.1063/1.1144419
  3. Morikawa, H. and Goto, K., 1988, "Reproducible sharp-pointed tip preparation for field ion microscopy by controlled AC polishing," Rev. Sci. Instrum. Vol. 59, No. 10, pp. 2195-2197. https://doi.org/10.1063/1.1139985
  4. In, C. H., Kim, G. M., and Chu, C. N., 2001, "Fabrication of tungsten probe using electro-chemical etching," J. Kor. Soc. Prec. Eng., Vol. 18, No. 2, pp. 111-118.
  5. Lim, Y. M., Lim, H. J., and Kim, S. H., 2001, "Fabrication of microshafts using electrochemical process," J. Kor. Soc. Prec. Eng. Vol. 18, No. 3, pp. 169-174.
  6. Human, A. M., Roebuck, B., and Exner, H. E., 1998, "Electrochemical polarization and corrosion behavior of cobalt and Co (W, C) alloys in 1N sulphuric acid," Materials Sci. and Eng. A241, pp. 202-210.
  7. Kang, M. J., 2001, Production of tungsten carbide microshaft using electro-chemical machining, M.S. Dissertation, School of Mechanical and Aerospace Engineering, Seoul National University, Republic of Korea.
  8. Masuzawa, T. and Kimura M., 1991, "Electrochemical surface finishing of tungsten carbide alloy," Annals of the CIRP, Vol. 40, No. 1, pp. 199-202. https://doi.org/10.1016/S0007-8506(07)61967-2
  9. Kim, B. H. and Chu, C.N., 2007, "Electrochemical micro machining with ultra-short pulse," KSMTE, Vol. 16, No. 2, pp. 7-11.