• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.75-79
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• 1995

A cutting experiment using diamond tool was performed to make the die cabity which is composed of micro groove with mirror surface. Fine cutting depth was generated by the elastic recovery of the modified tool holder on the conventional M/C. Surface roughness and profile were investigated with cutting speed and depth and through the low cutting speed of 10mm/min, Rmax 0.005 .mu. m or less of machined surface could be achieved.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.6
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• pp.615-621
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• 2015

In this paper diamond wire cutting method has been proposed to cut the rock in the tunnel face. Diamond wire saw method could cut the rock from tunnel face with very minor vibration and noise. In this study rock cutting process has been simulated with FEM method by using LS-DYNA explicit non-linear finite element code. Normal load act as an prime factor when cutting the rock surface. For observing the effect of normal load on bead, several experiments has been conducted by varying normal loads on the bead. From each experiment, cutting rate has been calculated to compare the cutting rate with different load conditions. By increasing the normal load on bead, cutting rate increases drastically.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.34-38
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• 2000

The trend of cutting process today goes toward higher precision and higher efficiency. Many thermal/frictional troubles occur in high-speed machining of die and mold steels.In this paper, the thermal characteristics are evaluated in high sped ball end-milling of hardened steel(HRc42). Experimental work is performed on the effect of cutting environments on tool life and cutting temperature. Cutting environments involve dry, wet(20bar), compressed chilly air at -9$^{\circ}C$, compressed chilly air at -35$^{\circ}C$. The measuring technique of cutting temperature using implanted thermocouple is used. The cutting temperature is about 79$0^{\circ}C$, 35$0^{\circ}C$ and 54$0^{\circ}C$ in dry, wet and compressed chilly air at +9$^{\circ}C$, respectively. The tool life for compressed chilly air at -9$^{\circ}C$ is longer than all other cutting environments in experiment.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.236-241
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• 2000

In the present industry, there is not only the cutting of iron metal, but also the cutting of alloy aluminum, brass and plastic to wood(Paulownia). A variety of material is used and these industry is made need of the cutting material but lots of experiments processing is not enough at the moment. At this point, our team processed the basic experiment about influencing of cutting angle of bite concerned to manufacture in the turning of non-iron metal. Generally speaking, we recognized that there was occurrence of increase of rough surface with increasing of cutting angle in the non-iron metal. but in the cutting of wood we knew, there was special change with change of cutting angle.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.3
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• pp.129-134
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• 1989

This experiment was conducted to evaluate the effect of cutting frequency and nitrogen fertilization on th change of vegetation and the yield of dry matter on the different mixture combination of permanent pasture. 1. DM yield was increased as the increasing Arrhenatherum elntius but was decreased as the increasing Tkisetum fkavescens. 2. DM yield was unaffectdd by the different mixture combination of permanent pasture eventually. 3. In case of cutting frequency, 2-cutting showed higher DM yield than that of 3-cutting, and N-fertilization level showed significant increase in DM yield as the increasing N-level, especially 2-cutting block of N-3 showed the highest yield and 3-cutting block of N-l showed the lowest yield. 4. Mixture combination, N-level and cutting frequency did not show significant changes in DM yield of permanent pasture eventually.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.75-80
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• 1991

The purpose of this experiment was in order to detect the effect of cutting height on the growth and thatch accumulation in Zoysio japonica Cutting height treatments were 2.5, 3.8, 5.1cm and no cutting, respectively. The results were obtained as follows : 1.Cutting treatments great]y affected to the growth of Zoysia japonica and thatch accumulation. 2.The dry weight of Leaf and shoot had the highest at 5.1cm. So 5.1cm treatment was desirable level for the top growth of Zoysia japonica 3.The dry weight of leaf, shoot, root and coverage of control were obtained the higher than cutting treatments. 4.The dry weight of thatch of control were less than cutting treatments, and 5.1cm treatment were more than tow cutting height. 5.Retationships of dry weight of thatch with thatch depth and C/F ratio were positive significant differences at 5% level. 6. Relationship between dry weight of shoot and coverage showed a positive significant difference at 5% level.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2001.11b
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• pp.35-42
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• 2001

In order to obtain basic information for pure line breeding of hemp which is effective on the pure line preservation and propagation, three varieties were investigative from 1995 to 1996 at Mokpo Experiment Station, Honam Agriculture Experiment Station, and cutting parts, cutting times, cutting length and storage duration after cutting of plant were observed. Higher rooting ratio were observed in cutting of shoot and later branch, in July 5, optimum harvesting time and 5 days after harvesting time, in shorter storage duration,0 and 2 days. Also there were the highest rooting ratio increased by from 12% to 16% in shorter cutting of 10cm than 15cm long cutting in shoot, lateral branch and stem cuttings. Hemp cv. Korea showed higher rooting ratio than the other varieties, Japan and Turkey. Therefore, it was concluded that hemp, a dioecious plant, could be effectively propagated for the pure lines by cutting method, especially in cv. Korea.

• Journal of Computational Design and Engineering
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• v.2 no.4
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• pp.233-247
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• 2015

In this paper, the cutting force calculation of ball-end mill processing was modeled mathematically. All derivations of cutting forces were directly based on the tangential, radial, and axial cutting force components. In the developed mathematical model of cutting forces, the relationship of average cutting force and the feed per flute was characterized as a linear function. The cutting force coefficient model was formulated by a function of average cutting force and other parameters such as cutter geometry, cutting conditions, and so on. An experimental method was proposed based on the stable milling condition to estimate the cutting force coefficients for ball-end mill. This method could be applied for each pair of tool and workpiece. The developed cutting force model has been successfully verified experimentally with very promising results.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.239-244
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• 1999

Radial immersion ratio is an important factor to determine the threshold in face milling and should be estimated in process for automatic force regulation. In this paper, presented is a method of on-line estimation of radial immersion ratio using cutting force. When a tooth finishes sweeping, sudden drop of cutting forces occurs. These force drops are equal to the cutting forces that act on a single tooth at the swept angle of cut and can be acquired from cutting force signals in feed and cross-feed directions. The ratio of cutting forces in feed and cross-feed directions acting on the single tooth at the swept angle of cut is a function of the swept angle of cut and the ratio of radial to tangential cutting force. In the research, it is found that the ratio of radial to tangential cutting force is not affected by cutting conditions and axial rake angle. Therefore, the ratio of radial to tangential cutting force determined by just one preliminary experiment can be used regardless of the cutting conditions. Using the measured cutting forces and predetermined ratio, the redial immersion ratio is estimated. various experiments show that the radial immersion ratio can be estimated by the proposed method very well.

• Design & Manufacturing
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• v.16 no.3
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• pp.39-43
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• 2022

In this study, we designed an vibration cutting tool that can achieve improvements such as low cutting force, interrupted chip evacuation and better surface quality of cutting performance to obtain high-quality surface roughness and improvement of tool wear, which is an issue in the machining of high-hardness mold steel. Among the resonance frequency modes of the vibration cutting tool, the bending mode was used to maximize the driving amplitude of the vibration tool tip, and the resonance frequency was confirmed through the finite element method. After measuring the actual resonant frequency of the designed tool using an optical fiber sensor, the cutting force and machining surface of vibration cutting and conventional cutting were compared and analyzed in the turning process of high hardness mold steel (STAVAX). As a result of the experiment, the cutting force was reduced by about 20 % compared to the conventional cutting process, and the surface roughness was also improved by about 60 %. This study suggested that the tool wear and surface quality of high-hardness steel can be improved through the vibration cutting method in the machining of high hardness mold steel.