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Son, Sung-Gyun;Han, Sol-Yi;Sung, In-Ha;Kim, Wook-Bae
- Transactions of the Korean Society of Mechanical Engineers B
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- v.37 no.12
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- pp.1159-1165
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- 2013
Powder blasting, which is an efficient micromachining method for glass, silicon, and ceramics, has a critical disadvantage in that the surface finish is poor owing to the brittle fracture of materials. Low-pressure waterjet machining can be applied to smoothen the rough surface inside the blasted structure. In this study, the surface roughness and sectional dimension of micro-channels are observed during the repetitive application of a waterjet to blasted micro-channels. The asperities and subsurface cracks created by blasting are removed by waterjet machining. Along with the surface roughness, it is found that the sectional dimension increases and the edges of the finished micro-channel become slightly round. Finally, a microfluidic chip is machined by the blasting-waterjet process and a transparent microfluidic channel is obtained efficiently.
https://doi.org/10.3795/KSME-B.2013.37.12.1159 인용 PDF KSCI

Byung-Won Min
- Journal of Internet of Things and Convergence
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- v.9 no.3
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- pp.93-98
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- 2023
In this paper, an artificial neural network based on simulated annealing was constructed. The mapping relationship between the parameters of micro-scaled flow channels electrochemical machining and the channel shape was established by training the samples. The depth and width of micro-scaled flow channels electrochemical machining on stainless steel surface were predicted, and the flow channels experiment was carried out with pulse power supply in NaNO3 solution to verify the established network model. The results show that the depth and width of the channel predicted by the simulated annealing artificial neural network with "4-7-2" structure are very close to the experimental values, and the error is less than 5.3%. The predicted and experimental data show that the etching degree in the process of channels electrochemical machining is closely related to voltage and current density. When the voltage is less than 5V, a "small island" is formed in the channel; When the voltage is greater than 40V, the lateral etching of the channel is relatively large, and the "dam" between the channels disappears. When the voltage is 25V, the machining morphology of the channel is the best.
https://doi.org/10.20465/KIOTS.2023.9.3.093 인용 PDF

Oh, Kwang-Hwan;Lee, Min-Kyu;Jeong, Sung-Ho
- Korean Journal of Optics and Photonics
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- v.17 no.5
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- pp.437-446
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- 2006
A fabrication method fur high-aspect-ratio microchannels in stainless steel using laser-assisted thermochemical wet etching is reported in this paper. The fabrication of deep microchannels with an aspect ratio over ten is realized by applying a multiple etching process with an optimization of process conditions. The cross-sectional profile of the microchannels can be adjusted between rectangular and triangular shapes by properly controlling laser power and etchant concentration. Excellent dimensional uniformity is achieved among the channels with little heat-affected area. Microchannels with a width ranging from 15 to $50{\mu}m$ can be fabricated with an aspect ratio of ten and a pitch of 150 m or smaller. The effects of process variables such as laser power, scan speed, and etchant concentration on the fabrication results, including etch width, depth, and cross-sectional profile are closely examined.
https://doi.org/10.3807/KJOP.2006.17.5.437 인용 PDF KSCI

Bahk, Yeon-Kyoung;Park, Kang-Su;Kim, Hyung-Hoon;Shin, Bo-Sung;Ko, Jong-Soo;Go, Jeung-Sang
- Journal of the Korean Society for Precision Engineering
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- v.27 no.7
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- pp.87-93
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- 2010
This paper presents an evaluation of efficiency on glass precision machining by using abrasive water-jet machine. In this study, problems of conventional water-jet machining are examined experimentally and are analysized numerically. Especially, the reason of whitening on the machined surface of biochip glass is determined. It is found that the mass flow rate of abrasive input and transverse speed of water-jet are key parameters to control the direct machining of micro hole and channel on a glass substrate. Based on results of experimental analysis, possibility of direct fabrication of micro holes and channels on a glass substrate is successfully confirmed.
PDF KSCI