• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1893-1896
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• 2003

This research aimed to fabricate a micro structure using micro electrochemical machining (${\mu}$-ECM). with a view to that the theory of ${\mu}$-ECM is established accurately in a different way of conventional electrochemical machining. In details, if the impedance is existed in the system, it is difficult to analyze the micro electrochemical reaction efficiently in polarization curve using a potentiodynamic test. Hence, this research investigates the relationships between impedance and electric current measuring with a potentiostatic test applying to a pair or electrode as a constant potential. And this paper examines the influence of temperature of electrolyte on polarization curve for the quantitative analysis of electrochemical reactions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.585-588
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• 2003

As the advance in technology requires micro mechanical systems, the production methods for micro parts are of a great interest of many researchers. Although MEMS is one of the most popular methods. it can only produce 2D microstructures. The micro manufacturing with micro-mill and micro-lathe has a great potential for producing arbitrary 3D shapes and are being researched. In this paper, a PC based 5-axis milling machine with high precision was developed. To evaluate the machine performance, micro ribs and micro columns were machined. The machining experiments of micro impeller and micro turbine blade confirmed the possibility of micro system manufacturing by using the developed milling machine.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.685-686
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.181-184
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• 2002

In these day, fabrication technologies for micro parts become more important with the increase of interest on microsystem and developed through the various approaches in the whole world. Among these technologies; micro mechanical machining is one of the most effective methods for the fabrication of micro parts. In this study, we fabricated micro shafts using micro endmill and micromachining system and measured the cutting force at the process. Also, Based on the data, we simulated the deformation of micro shafts due to the cutting force. Through the simulation results, it was verified that the cutting force at the process is enough to cause dimensional error at the micro shafts.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.4
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• pp.97-101
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• 2002

Recently, the need for transporting and manipulating minute amount of fluids in microscale channels (so-called micro-fluidics) has been increasing, especially in biotechnology and biochemical processing. This work demonstrates that the so-called mechano-chemical process which consists of mechanical abrasive action combined with chemical process can be used to f뮤ricate micro-fluidic channels more rapidly and cost effectively than other methods. In this work, capillary filling of fluids in micro-channels was investigated by theoretical approaches and experiments. From the experimental results, it is expected that a complex micro-fluidic system can be fabricated using the micro-fabrication technique and microsystem packaging method described in this work.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.7
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• pp.133-140
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• 2002

Ultrasonic Machining (USM) is widely used in cutting of non-conductive, brittle workpiece materials such as engineering ceramics. However, USM has a limitation in its application to micro machining because problems are occurred in attaching micro tools to the machine and maintaining high precision. Therefore Micro Ultrasonic Machining (MUSM) with WEDM is proposed in this research. The experiments are produced as the change of shaft diameter and abrasive size.

• Transactions of Materials Processing
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• v.11 no.7
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• pp.608-613
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• 2002

An ultrasonic machining process is efficient and economical means for precision machining of glass and ceramic materials. However, the mechanism of the process with respect to the crack initiation and propagation and the stress development in the ceramic workpiece subsurface arc still not well understood. In this research, we have investigated the basic mechanism of ultrasonic machining of ultrasonic machining of glass by the experimental approach. For this purpose, we designed and fabricated the desktop micro ultrasonic machine. The feed is controlled precisely by using the constant load control system. During machining experiments, the effects of abrasive characteristics and machining conditions on the surface roughness and the material removal rate are measured and compared.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1025-1028
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• 2002

In this paper, a micro-turning lathe is introduced for micro machining of aluminum rod. To give feed motion, stepwise motion[2] actuators are used instead of the conventional inchworm mechanism. These are consisted of two Piezoelectric ceramics; one is for feeding the slider, and the other is for clamping the slider in the guide way of the body. The guide is V-form. The linearity and positional accuracy of the actuators is good enough far high precision motion. Since the system is more compact than the conventional system using three Piezoelectric ceramics, it is applicable for the micro-machine or MEMS unit. To fabricate the lathe, a small spindle unit with ball bearings of diameter of 10 millimeter is built-up on the top the slider. The motion is feed backed with miniaturized linear encoder attached each axis slider. The diamond tool bite is used for cutting tool. The machining is tried to make small diameter rod. The possible diameter that can be machined in this machine is presented as well as chip formation, surface roughness, and machinability.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.75-78
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• 1995

This paper presents the feasibility of laser ablation process in 3-D micro machining of MEMS (micro Electro Mechanical System)parts. The micro machining characteristics of polymer(Energy fluence, pulse repetition rate, number of pulse, ablation rate)are investigated and 3-D micro machined samples are demonstrated.

• Korean Journal of Metals and Materials
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• v.46 no.6
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• pp.390-401
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• 2008

The objective of this study is to evaluate various machining characteristics of AlN-hBN machinable ceramics in micro end-milling process for its further application. First, AlN based machinable ceramics with hBN contents in the range of 10 to 20vol% were prepared by hot-pressing. Material properties of the composites, such as relative density, Vickers hardness, flexural strength, Young's modulus and fracture toughness were measured and compared. Then, micro end-milling experiments were performed to fabricate micro channels using prepared system. During the process, cutting forces, vibrations and AE signals were measured and analyzed using applied sensor system. Machined micro channel shapes and surface roughness were measured using 3D non-contact type surface profiler. From the experimental results, it can be observed that the cutting forces, vibrations and AE signal amplitudes decreased with increasing hBN contents. Also, measured surface roughness and profiles were improved with increasing hBN contents. As a result of this study, optimum machining conditions can be determined to fabricate desired products with AlN-hBN machinable ceramics based on the experimental results of this research.