Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Design and Fabrication of a Micro-Heat Pipe with High-Aspect-Ratio Microchannels

고세장비 미세채널 기반의 마이크로 히트파이프 설계 및 제조

  • 오광환 (광주과학기술원 기전공학과) ;
  • 이민규 (광주과학기술원 기전공학과) ;
  • 정성호 (광주과학기술원 기전공학과)
  • Published : 2006.09.01
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Abstract

The cooling capacity of a micro-heat pipe is mainly governed by the magnitude of capillary pressure induced in the wick structure. For microchannel wicks, a higher capillary pressure is achievable for narrower and deeper channels. In this study, a metallic micro-heat pipe adopting high-aspect-ratio microchannel wicks is fabricated. Micromachining of high-aspect-ratio microchannels is done using the laser-induced wet etching technique in which a focused laser beam irradiates the workpiece placed in a liquid etchant along a desired channel pattern. Because of the direct writing characteristic of the laser-induced wet etching method, no mask is necessary and the fabrication procedure is relatively simple. Deep microchannels of an aspect ratio close to 10 can be readily fabricated with little heat damage of the workpiece. The laser-induced wet etching process for the fabrication of high-aspect-ratio microchannels in 0.5mm thick stainless steel foil is presented in detail. The shape and size variations of microchannels with respect to the process variables, such as laser power, scanning speed, number of scans, and etchant concentration are closely examined. Also, the fabrication of a flat micro-heat pipe based on the high-aspect-ratio microchannels is demonstrated.

Keywords

References

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