• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.2
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• pp.37-43
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• 2004

High speed machining is a machining process which cuts materials with the fast movement and rotation of a spindle in a machine tool. It reduces machining time because of the high feed and the high speed of a spindle. In addition it gets rid of post processes for high precision machining. When the high speed machining is applied to especially hardened steel, operators should select the proper parameters of machining. This can produce machining surfaces which is qualified with good surface roughness. This paper presents a method for selecting machining parameters to minimize surface roughness with high speed machining in cutting the hardened steels. Experimental data for surface roughness are collected in a machining shop based on the cutting feed and the spindle rotation. The data fits in hi-cubic polynomial surface of mathematical form. From the model this research minimize the surface roughness to find the optimal values of the feed and the spindle speed. This paper presents a program which automatically generates optimal solutions from the raw data of experiments.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.765-768
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• 2005

Ball end milling is widely used in machining free surfaces. It is important to predict machining forces in this machining. In this study, cutting forces are predicted for different machining conditions in ball end mill contouring machining. These cutting forces influence tool deflection. In this study tool deflection is calculated for various cutting conditions. The model developed in this study can be used to predict machining accuracy in contouring machining.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1202-1205
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• 2005

Micro hole is one of basic elements for micro device or micro parts. By micro ECM, micro holes less than $50\mu{m}$ in diameter can be machined easily. Machining characteristics of micro ECM were investigated according to machining conditions such as electrolyte concentration and pulse conditions. From the investigation, optimal machining conditions were suggested for micro ECM of stainless steel. For the micro machining with high resolution, the change of machining gap should be predicted. By using electrochemical principle equations, the change of machining gap was simulated.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.12
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• pp.42-49
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• 2007

When micro holes are machined by EDM, machining characteristics of machined holes are changed according to the machining conditions. Typical machining conditions are the kind of dielectric fluids, capacitance and ultrasonic vibrations. They influence electrode wear, machining time, radial clearance and taper angle. In this paper, machined holes whose depths are 300, 500, $1000\;{\mu}m$ are observed for each machining conditions. Using deionized water as a dielectric fluid makes electrode wear small, machining time short, radial clearance large and taper angle small. High capacitance makes electrode wear high. Ultrasonic vibrations make electrode wear large, machining time short, radial clearance small and taper angle small. From the results of experiments, the optimal machining conditions were obtained to machine highly qualified micro holes.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.12 s.189
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• pp.38-45
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• 2006

In this work, optimal finish machining condition considering total time for mold or electrode manufacturing was investigated. First, manual finishing time according to the machining condition was analyzed for the work material. The effect of runout and phase shift of tool path on surface finish was also considered in those analyses. Secondly, optimal manual finishing processes were determined for various machining conditions. Finally, finish machining time and corresponding manual finishing time were taken into account for the estimation of the total time of manufacturing mold. Though small feed per tooth and pick feed reduced the manual finishing time, the finish machining time increased in such conditions. With a machining condition of feed per tooth of 0.2 mm and pick feed of 0.3 mm, the minimum total time of manufacturing mold was achieved in our machining condition.

• Journal of Institute of Convergence Technology
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• v.4 no.2
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• pp.41-45
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• 2014

Micro fabrication technologies of aluminium have been required to satisfy many demands in technology fields. Pulsed laser beam machining can be an alternative method to accomplish the micro machining of aluminium. Pulsed laser beam can be applied to micro machining such as micro drilling and milling. Using pulsed laser beam, the machining characteristics of aluminium in micro drilling and milling were investigated according to average power, repetition rate, moving speed of spot. The laser beam machining with the optimal conditions can achieve precise micro figures. As a result, micro pattern, text and structures on aluminium surface was successfully fabricated by pulsed laser beam machining.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.393-396
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• 1997

High-speed machining is one of the most effective technologies to improve productivity. Because of the high speed and high feed rate, high-speed machining can give great advantages for the machining of dies and molds. This paper describes on the improvement of machining accuracy in high-speed machining. Depth of cut and feed rate are control factors. The effect of the control factors on machining accuracy is investigated using two-way factorial design.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.3
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• pp.357-362
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• 2003

Recently, the demand for advanced technology of high precision and high efficiency processing of hard materials such as inconel is increasing with progress of industrial goods. However, the machinability of inconel is very inferior to the other conventional industrial materials and the machining technology for inconel involves many problems to be solved in machining accuracy, machining efficiency, etc. Therefore it is needs to establish the machining technology. The purpose of this study is to develop an advanced ultrasonic vibration machining technology for inconel, using the 60KHz and 75KHz high frequency, amplitude about 8${\mu}{\textrm}{m}$ and 4${\mu}{\textrm}{m}$, respectively. As the result, this new ultrasonic vibration machining is reasonable and suitable for the high efficient. accuracy machining method of inconel.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.1
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• pp.22-27
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• 2004

Recently, environmental pollution has become a significant problem in industry and many researchers have investigated in order to preserve the environment. Environmentally conscious machining and technology have more important position in machining process, because cutting fluid has bad influence on the environment in milling process. This research is the experimental study on high speed machining of aluminum alloys through environmentally conscious machining. In this study, the surface roughness and chip appearance was investigated in the machining of aluminum alloys by dry machining, using cutting fluid and oil mist.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.98-103
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• 2012

One of the problems in the grinding process using the machining center(MC) with a small diametric wheels is machining error due to decrease of the quill diameter. In this thesis, side-cut grinding is performed with a vitrified bonded CBN wheel on the machining center to establish the basis of the grinding using MC. The grinding force and machining error are investigated experimentally for the change of the machining condition. It is possible to estimate the machining performance by the ratio of the setting depth of cut and actual depth of cut. In addition, the relation between normal grinding force and machining error is presented by the experimental formula.