• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.371-374
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• 2003

The bending process for the "ㄱ" section product can be developed by the hot metal extrusion machine with the two punches moving in the different velocity. The bending phenomenon can be controlled by difference of velocity at the die exit section by the different velocity of billets through the two-hole container. The results of the experiment show that "ㄱ" section product can be bended by the extrusion process and that the curvature of the product can be controlled by the velocity of punch and that the defects such as the distortion of section and the thickness change of the product and the folding and wrinkling of the product did not happen after the bending processing by the extrusion bending machine.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.04a
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• pp.107-112
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• 1997

In this study of made Autmation system is moving linear transfer system for mainly forming of small electronic unit and other at press line. This system for loading and unloading a workpiece has been installed in a press in order to load and unload a workpiece from a press die. Main Control method be used PLC. It took data of input from each sensor and send signal of output to actuator by sequence program also, we try to Characteristics test of this system has good condition when operating with raser measurmant.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.3
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• pp.42-51
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• 1999

An experimental modeling of cutting and structural dynamics and the on-line detection of malfunction process is substantial not only for the investigation of the static and dynamic characteristics of cutting process but also for the analytic realization of diagnostic systems. In this regard, We have discussed on the comparative assessment of two recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision round shape machining such as turning, drilling and boring in mold and die making. In this study, simulation and experimental work were performed to show the malfunctioned behaviors. For this purpose, two new recursive approach (REIVM, RLSM) were adopted fur the on-line system identification and monitoring of a machining process, we can apply these new algorithm in real process for the detection of abnormal machining behaviors such as chipping, chatter, wear and round shape lobe waviness.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.10a
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• pp.156-160
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• 1996

In this study of made Unloader is moving linear transfer system for mainly plastic working or forming of small electronic unit and other at press line. This machine for lading and unloading a workpiece has been installed in a press in order to load and unload a workpiece form a press die. Control method be used PLC. it took data of input from each sensor and send signal of output to actuator today we have a lot of problem at work of press line. most of press work be operated by human so they often hurted terreble accident by press machine. Because press working system in automotive factories are now changing over to a transfer press working system this Unloader will give more easily and speedy production and manpower saving less of pruduction cost high perfomance

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03b
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• pp.9-13
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• 1999

In order to investigate the effect of flange wrinkling on the wall break of a deep drawn rectangular cup, experiments and simulation were done. The effect of the wrinkling height on drawing force and wall break for a moving blank holder system with spacer were studied by setting a fixed clearance between the drawing die and the blank holder. Simulation and experimental results showed that wall break could be provoked by the flange wrinkling. As the wrinkling height increased, the punch force grew. The maximum punch force was obtained at its final stage of stroke.

• Elastomers and Composites
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• v.55 no.1
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• pp.40-45
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• 2020

In this study, the mechanical and flame-retardant properties of ethylene-propylene-diene-termonomer (EPDM) based rubber compounds and various other environmentally friendly inorganic flame retardants were investigated. Alumina trihydrate (ATH) and magnesium hydroxide (MDH) were used as inorganic flame retardants. The mechanical properties after thermal oxidation aging and the flame-retardant properties of the EPDM compounds were measured using a moving die rheometer, a universal testing machine, a compression set, and a UL 94 V flammability test. We focused on how the properties were affected by the type and amount of flame retardants. The results demonstrated that the optimal mechanical and flame-retardant V-0 grade properties were obtained at an ATH content of 200 phr.

• Elastomers and Composites
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• v.55 no.3
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• pp.176-183
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• 2020

Silica-styrene butadiene rubber (Silica-SBR) compounds have been used in the preparation of tire treads. The silica dispersibility of silica-SBR compounds is related to the processability, mechanical properties, and wear resistance of tires. Recently, in order to improve the silica dispersibility of the silica-SBR compounds, the wet masterbatch (WMB) process was introduced, which is a method of mixing rubber in the water phase. We aimed to improve the silica dispersibility of the silica-SBR compounds by preparing a silica dispersant applicable to the WMB process. For this purpose, cellulose, 2-hydroxyethyl cellulose, and cellulose acetate were employed as a silica dispersant. The silica dispersibility of the compounds was measured by a moving die rheometer. Improvement in the processability of silica-SBR compounds was evaluated by the Mooney viscometer. The wear resistance of silica-SBR compounds using a cellulose dispersant was improved by up to 29%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1652-1657
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• 2015

Recently the improvement in vehicle performance trend to increase in accordance with the weight of this part. Outer tie rod is small when compared to the other vehicle part by weight, but there is a need to reduce the weight of the outer tie rod in order to improve fuel efficiency of the vehicle. Therefore, from previous studies, a model of outer die rod is proposed using Design of Experiments and Meta model satisfying the buckling performance. Outer tie rod are manufactured through forging process, in this study, we compare the size of the forming load in accordance with the change in the moving speed through the die forging analysis of the outer tie rod on the basis of the actual molding process.

• Design & Manufacturing
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• v.14 no.3
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• pp.44-49
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• 2020

One of display trends today is development of high pixel density. To get high PPI, a small size of pixel must be developed. RGB pixel is arranged by evaporation process which determines pixel size. Normally, a fine metal mask (FMM; Invar alloy) has been used for evaporation process and it has advantages such as good strength, and low thermal expansion coefficient at low temperature. A FMM has been manufactured by chemical etching which has limitation to controlling the pattern shape and size. One of alternative method for patterning FMM is laser micromachining. Femtosecond laser is normally considered to improve those disadvantages for laser micromachining process due to such short pulse duration. In this paper, a femtosecond laser drilling for thickness of 16 ㎛ FMM is examined. Additionally, we introduce experimental results for controlling taper angle of hole by vibration module adapted in laser system. We used Ti:Sapphire based femtosecond laser with attenuating optics, co-axial illumination, vision system, 3-axis linear stage and vibration module. By controlling vibration amplitude, entrance and exit diameters are controllable. Using vibrating objective lens, we can control taper angle when femtosecond laser hole drilling by moving focusing point. The larger amplitude of vibration we control, the smaller taper angle will be carried out.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.204-207
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• 2001

The bending process for the circular curved tube and rectangular curved tube with fins can be developed by the hot metal extrusion machine with the multiple punches moving in the different velocity. The bending phenomenon can be controlled by the two variables. The one of them is the difference of velocity at the die exit section by the different velocity of billets through the multi-hole container. The other is the one by the different hole diameter. The results of the experiment show that the circular curved tube with fins and rectangular curved tube with pins can be formed by the extrusion process and that the curveture of the product can be controlled by the velocity of punch and diameter of container hole and that the defects such as the distortion of section and the thickness change of the wall of tube the folding and wrinkling of thin tube and fins did not happen after the bending processing by the extrusion bending machine.