• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.155-160
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• 2001

In the use of glass fiber reinforced plastics(GFRP) it is often necessary to cut the components, but the cutting of GFRP is often made difficult by the delamination of the compositions and short tool life. Experimental investigation was conducted to evaluate the chip formation of the glass fiber reinforced plastics during orthogonal cutting. The chip formation process, cutting force, and thrust force were studied. The chip formation processes were studied through the use of quick-stop device. Chip-tool contact areas were obtained with the use of the quick-stop device, and observed using optical microscopy after polishing. Cutting force and thrust force were measured through the use of the tool dynamometer.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.2
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• pp.44-52
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• 2003

This research suggests a cutting force model for the ball end milling processes. This model includes the effect of tool run out and tool deflection. In the proposed model, the flutes of ball end mills are considered as series of infinitesimal elements and each cutting edge is assumed to be straight for the analysis of the oblique cutting process, in which the small cutting edge element has been analyzed as an orthogonal cutting process n the plane including the cutting velocity and the chip-flow vector. Therefor, the cutting forces can be calculated through the model using the orthogonal cutting data obtained from the orthogonal cutting test. In order to enhance the performance of the model, the flutes of ball end mill are defined to keep geometric consistency at the peak of the ball part and the junction with the end mill part. The divided infinitesimal cutting edges are regulated to be even lengths. Some experiments show the validity of the developed model in the various cutting coalitions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1012-1015
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• 2001

The purpose of this paper is to evaluate the specific cutting energy characteristics during turning SM45C steel. Using the orthogonal array method the specific cutting energy has been predicted. And the significance of the equation is checked by ANOVA test. Predicted values of specific cutting energy are well concide with the measured ones. When the feed rate becaomes larger than 0.5mm/rev, predicted specific cutting energy increases.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.2
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• pp.89-94
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• 2001

This paper presents a study of surface roughness prediction model by orthogonal design in turning operation. Regression analysis technique has been used to study the effects of the cutting parameters such as cutting speed, feed depth of cut, and nose radius on surface roughness. An effect of interaction between two parameters on surface roughness has also been investigated. The experiment has been conducted using coated tungsten carbide inserts without cutting fluid. The reliability of the surface roughness model as a function of the cutting parameters has been estimated. The results show that the experimental design used in turning process is a method to estimate the effects of cutting parameters on sur-face roughness.

• Steel and Composite Structures
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• v.19 no.6
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• pp.1467-1481
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• 2015

This paper presents a contribution to improving an analytical thermo-mechanical modeling of Oxley's machining theory of orthogonal metals cutting, which objective is the prediction of the cutting forces, the average stresses, temperatures and the geometric quantities in primary and secondary shear zones. These parameters will then be injected into the developed model of Karas et al. (2013) to predict temperature distributions at the tool-chip-workpiece interface. The amendment to Oxley's modified model is the reduction of the estimation of time-related variables cutting process such as cutting forces, temperatures in primary and secondary shear zones and geometric variables by the introduction the constitutive equation of Johnson-Cook model. The model-modified validation is performed by comparing some experimental results with the predictions for machining of 0.38% carbon steel.

• Journal of the Korean Society of Safety
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• v.16 no.3
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• pp.135-142
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• 2001

This study discusses frequency analysis based on the frequency spectrum and process characterization in orthogonal cutting of Fiber-matrix composite materials. A sparsely distributed idealized composite material, namely a glass reinforced polyester(GFRP) was used as workpiece The present method employs a force sensor and the signals from the sensor are processed using the fast Fourier transform(FFT) technique. The experimental correlations between the different chip formation mechanisms and power spectrum me established. Effects of fiber orientation, cutting parameters and tool geometry on the cutting mechanisms me also discussed.

• Journal of the Korean Society of Safety
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• v.23 no.6
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• pp.1-6
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• 2008

Machine operator and quality are affected by chip during cutting process to product machine parts. This paper presents a study of the influence of cutting conditions on the surface roughness obtained by turning using Taguchi method for safety of turning operator. In the machining of titanium alloy, high cutting temperature and strong chemical affinity between the tool and the work material are generated because of its low thermal conductivity and chemical reactivity. Therefore titanium alloys are known as difficult-to materials. An orthogonal array, the signal-to-noise ratio, the analysis of variance are employed to investigate the cutting characteristics of implant material bars using tungsten carbide cutting tools of throwaway type. Also Experimental results by orthogonal array are compared with optimal condition to evaluate advanced reliability. Required simulations and experiments are performed, and the results are investigated.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.1
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• pp.74-83
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• 1991

A study on the Correlation of Orthogonal Cutting Parameter (Cutting speed, Depth of cut, Feed Rate) and Acoustic Emission Signal. It is well known that acoustic emission (AE) is the emission of elastic wave resulting from the deformation and fracture of materials. This study estabished correlation of orthogonal cutting parameter and AE signal, and researched into in-process monitoring of tool wear and failure. The results are as follow; 1. AE RMS was under the influence of cutting speed but hardly influenced by depth of cut and feed rate. 2. AE RMS was under the influence of flank wear. 3. AE count rate increased by increased cutting speed. 4. AE RMS value was rapidly increased in 130 m flank wear.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.2926-2935
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• 1993

Chip breaker selection analysis, only being possible through experimental process, was obtained by a applied equation which used an orthogonal cutting model and a basic chip deformation. This equation could present an analysis of the chip breaking phenomena without the use of an actual experimetal method, and it was applied to computer simulation and proved the validity of theory through actual experiments. From these results, an efficient method for finding the optimum conditions of chip breaking was found through an optimized theory being applied to basic program. A finite element model for simulating chip breaking in orthogonal cutting was developed and discussed. By simulation the animation of chip breaking is observed in process on the computer screen.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.988-991
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• 2001

Plastically deformed layer influences the mechanical property of the mechanical element such as creep hardening, microscopical crack and stress corrosion destruction. Therefore, the property so called the surface integrity has to be considered, and the machined surface including plastic deformation, distribution of stress has to be conducted quantitatively. This paper explains the orthogonal cutting, and made an orthogonal cutting model using the finite element method, then analyzed cutting power, plastic deformation of workpiece. It introduces the developed subsequent recrystallizations technique for measurement of the plastic strain of machined surface, and verified the technique.