• Journal of Surface Science and Engineering
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• v.34 no.4
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• pp.337-341
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• 2001

TiN coating of high speed end mill is recently generalized. The study of coating layer using ion plating is mainly about the coating method and the why of the longer life of coated tools. In CNC machning process, metal cutting isn't carry out until the tools including the end-mill and so on are fractured. Namely, it is difficult precision processing when the cutting force of the cutting tool is near the limit the fracture cutting force. So, the estimate of the life by wear and fracture is important. Therefore, this study is about the method to estimate the capacity of the coating layer in relation to the tendency of cutting force and the influence of the cutting capacity of coated end-mill by the condition N2, Ar, temperature. The cutting length is in inverse proportion to the cutting force ratio. So, the life of the TiN coated end mill can be predicated by the ratio of the increase of the cutting force.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.208-213
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• 2001

High speed milling(HSM) is one of the emerging cutting process having tremendous potential not only in increased metal removal rates but also in improved surface finish, burr free edge, dimensional accuracy and a virtually stress free component after machining. The High efficiency and accuracy in machining of die/mold materials can be obtained in high speed machining, so it is necessary to analytic the mechanism of high speed cutting process : cutting force, acoustic emission signal.

• Advances in Computational Design
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• v.5 no.1
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• pp.13-34
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• 2020

As small size and complex metal machining components demand increases, cutting processes in microscale become necessary. Ball-end milling is a commonly used finishing process, which nowadays can be applied in the microscale size. Surface quality and dimensional accuracy are two basic parameters that affect small size components in their assembly and functionality. Thus, good quality can be achieved by optimizing the cutting conditions of the procedure. This study presents a 3D simulation model of ball-end milling in microscale developed in a commercial CAD software and its optical and computing results. These carried out results are resumed to surface topomorphy, surface roughness, chip geometry and cutting forces calculations that arising during the cutting process. A great number of simulations were performed in a milling machine centre, applying the discretized kinematics of the procedure and the final results were compared with measurements of Al7075-T651 experiments.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.1145-1151
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• 2022

A hybrid cutting using both plasma and end mill was developed for safe and efficient dismantling of nuclear facilities. In this cutting method, a moving arc plasma heats up the workpiece before milling. Thermally softened part of the workpiece is then removed quickly and deeply with an end mill. For the cutting experiments, a three-axis numerical control (NC) milling machine was combined with a commercialized arc plasma torch and used to cut 25 mm thick stainless steel plates. Experimental results revealed that pre-heating by arc plasmas can improve the cutting volume per unit time higher than 40% by reducing the cutting load and increasing the cuttable depth when using an end mill without cutting fluids. These advantages of a hybrid cutting process are expected to contribute to quick and safe segmentations of metal structures with radioactively contaminated inner surfaces.

• Journal of the Korean Society for Precision Engineering
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• v.5 no.1
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• pp.40-49
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• 1988

The chip control problem is one of the important subjects to be studied in the metal cutting process. Especially, an important practical problem concerns the form of chips pro- duced in machining since this has important implications relative to : 1. Personal safety. 2. Possible damage to equipment and product. 3. Handling and disposal of swarf after machining. 4. Cutting forces, temperatures, and tool life. However, a dependable way to predict the form of chips in a wide range of cutting conditions has not been established satisfactorily. In this paper, the relationship between the form of chips and the ratios of cutting forces were studied experimentally. According to what the experiments have been carried out in the turning process the main results can be summarized as follows : 1. By use of the multiple linear regression model, emperical formulas which are suitable to wide ranges of cutting conditions with accuracy were obtained satisfactorily. 2. The correlations between the form of chips based upon the classification by Henriksen and the ratios of cutting forces, namely (feeding force/thrust force), (principal force/feeding force) were determined. 3. Using above results, the algorithms which predict the form of chips were constituted. With these algorithms, the form of chips in a wide range of cutting of cutting conditions can be predicted.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.18-21
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• 2002

As the mask design rules get smaller, the probability of the process failure becomes higher due to the narrow overlay margin between the contact and metal interconnect layers. To obtain the minimum process margin, a tabbing and cutting method is applied with the rule based optical proximity correction to the metal layer, so that the protection to bridge problems caused by the insufficient space margin between the metal layers can be accomplished. The side-lobe phenomenon from the attenuated phase shift mask with the tight design nile is analyzed through the aerial image simulation for test patterns with variation of the process parameters such as numerical aperture, transmission rate, and partial coherence. The corrected patterns are finally generated by the rules extracted from the side-lobe simulation.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.209-212
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• 2002

As the mask design rules get smaller, the probability of the process failure becomes higher doc to the narrow overlay margin between the contact and metal interconnect layers. To obtain the minimum process margin, a tabbing and cutting method Is applied with the rule based optical\ulcorner proximity correction to the metal layer, so that the protection to bridge problems caused by the insufficient space margin between the metal layers can be accomplished. The side-lobe phenomenon from the attenuated phase shift mask with the tight design rule is analyzed through the aerial image simulation for test patterns with variation of the process parameters such as numerical aperture, transmission rate, and partial coherence. The corrected patterns are finally generated by the rules extracted from the side-lobe simulation.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.709-715
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• 2011

Chattering in cutting operations are usually a cumbersome part of the manufacturing process in mechanical. Particular, machining performance such as that of the boring process is limited by cutting condition at the movable components. Among various sources of chatter vibration, detrimental point in cutting condition is found a mechanical condition on overhang. It limits cutting speed, depth, surface roughness and tool wear failure as result because the all properties are varying with the metal removal process. In this case, we have to observe the resonance frequencies of a boring bar for continuous cutting. In the established research, boring bar vibration of cutting system has been measured with the aid of accelerometer. However, the inherent parameters of internal turning operations are severely limit for the real time monitoring on accelerometers. At this point, this paper is proposed other method for real time monitoring during continuous cutting with optical fiber at the inside of boring bar. This method has been used a plastic fiber in the special jig on boring bar by based on experimental modal analysis. In this study, improvement of monitoring system on continuous internal cutting was attempted using optical fiber sensor of inside type because usually chattering is investigated experimentally measuring the variation in chip thickness. It is demonstrated that the optical fiber sensor is possibility to measure of chattering with real time in boring process.

• Journal of the Korean Graphic Arts Communication Society
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• v.9 no.1
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• pp.45-51
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• 1991

Commercially available paper stickers, electrostatic stickers, and metal sticker generally involve process of printing on the substrate and die-cutting to peel the sticker off the release paper. Using plastisol ink and multi-layer screen printing technique, a process of non die-cutting sticker with same image on both sides was developed. It was also possible to prevent color mixing phenomena at image edge part by printing narrow lines of black ink along the borderline.

• Journal of Welding and Joining
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• v.5 no.1
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• pp.23-33
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• 1987

Plasma arc cutting is a fusion cutting process in which a gas constricted arc is employed to produce high temperature, high velocity jet at the workpiece. Even though the plasma arc cutting has been wid¬ely used in the industry, very little work has been done on the analysis of the process. In this paper, the kerf width was numerically analyzed by soving the temperature distribution in base metal under consideration of the latent heat effect. In modelling the heat flow problem, the heat intensity of the plasma arc was assumed to have a Gaussion distribution in the transverse direction and expone¬ntially decreasing in the thickness direction. The thermal efficiency and the heat input ratio of the top surface were experimentally deterimned for various thickness and cutting conditions, and used in numerical calculation of the kerf width. The experimental results were in eonsiderabely good agreement with the theoretically predicted kerf width.