• Proceedings of the KSME Conference
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• 2004.11a
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• pp.928-933
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• 2004

A new approach for modelling and simulation of the cutting forces in end milling processes is presented. In this approach, the cutting forces in end milling are modelled based on a predictive machining theory, in which the machining characteristic factors are predicted from input data of fundamental workpiece material properties, tool geometry and cutting conditions. In the model, each tooth of a end milling cutter is divided into a number of slices along the cutter axis. The cutting action of each of the slices is modelled as an oblique cutting process. For the first slice of each tooth, it is modelled as oblique cutting with end cutting edge effect, whereas the cutting actions of other slices are modelled as oblique cutting without end cutting edge effect. The cutting forces in the oblique cutting processes are predicted using a predictive machining theory. The total cutting forces acting on the cutter is obtained as the sum of the forces at all the cutting slices of all the teeth. A Windows-based simulation system for the cutting forces in end milling is developed using the model. Experimental milling tests have been conducted to verify the simulation system.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.3
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• pp.22-29
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• 2004

Runout causes severe differences among cutting force waveforms due to changes of rotational radii. Thus a runout model must be included in a cutting force model to simulate cutting force accurately. In this paper, a runout modeling method and a measurement method using a dialgauge were developed, which were easy to apply. To calculate runout parameters, a computer program algorithm which obtained runout parameters from measurement values was developed. Cutting force waveforms simulated from cutting force model considering runout effect and measured from experiments had good agreements for their wave size and order.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.3
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• pp.433-442
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• 1989

Owing to the development of CNC machine tools and automatic programing software, the milling process with ball-end mill has become the most widely used process where three-dimensional precision machining is important. In this study, the ball-end milling process has been analyzed and a cutting force model has been developed to predict the cutting force acting on the ball-end mill on given machining conditions. The development of the model is based on the analysis of geometry of a ball-end mill an the oblique cutting process. The cutting edges of ball-end mills are considered as a series of infinitesimal elements and the geometry of the cutting edge element each cutting edge element is straight. The oblique cutting process in the small cutting edge element has been analyzed as orthogonal cutting process in the plane containing the cutting velocity vector and chip-flow vector. Hence, with the orthogonal cutting data obtained from orthogonal turning test, the cutting forces can be predicted through the model. The predicted cutting forces has shown a fairly good agreement with the test results in various plane cutting conditions.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.11
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• pp.82-91
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• 1996

In this study, we put our object to carry out adaptive modeling of cutting process in turning system, and to find out the optimal cutting conditions to maximize material removal rate under some constraints. We used a back-propagation neural network to model the cutting process adaptively and a genetic algorithm to find out optimal cutting conditions. The experimental results show that a back-propagation neural network could model the cutting process effciently, and optimized cutting conditions for maximizing the material removal rate were obtained through the adaptive process model and genetic algorithms. Therefore, the proposed approach can be applied to the real machining system.

• Structural Engineering and Mechanics
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• v.61 no.4
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• pp.519-526
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• 2017

In the present paper, the effects of cutting parameters and coating material on the performances of cutting tools in turning of AISI 52100 steel are discussed experimentally. A comparative study was carried out between uncoated and coated (with TiCN-TiN coating layer) cermet tools. The substrate composition and the geometry of the inserts compared were the same. A mathematical model was developed based on the Response Surface Methodology (RSM). ANOVA method was used to quantify the effect of cutting parameters on the machining surface quality and the cutting forces. The results show that feed rate has the most effect on surface quality. However, cutting depth has the significant effect on the cutting force components. The effect of coating layers on the surface quality was also studied. A lower surface roughness was observed when using PVD (TiCN-TiN) coated insert. A second order regression model was developed and a good accuracy was obtained with correlation coefficients in the range of 95% to 97%.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.4
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• pp.87-96
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• 1996

On face milling operation a newly optimal tool, which can minimize the resultant cutting forces resulted from the cutting force model, was designed and manufactrued. Cutting experiments using the new and conventional tools were carried out and the cutting forces resulted from those tools were analyzed in time and frequency domains. The performance of the optimized cutter was tested through the dynamic cutting forces resulted form the newly designed tool are much reduced in comparision with those from the conventional tool. By reducing the dynamic cutting force fluctuations, machine tool vibrations can be reduced, and stable cutting operation can be carried out.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.10
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• pp.1069-1077
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• 2015

In tunnel excavation using blast, the wire saw rock cutting method generates a discontinuity perimeter around the center cut, and thus prevents blast vibration propagation to reduce vibration and noise. Therefore, the method is expected to be easy to use and economical compared with other methods. In this paper, the cutting mechanism of wire saw in tunnel excavation is investigated. A model describing the changes in cutting depth and wire saw shape inside a rock during cutting is established and validated for this purpose. Through a simulation using the model, the important characteristics of wire saw cut are investigated, and the influences of cutting conditions, such as wire saw tension, wire saw speed, feed speed, depth, and diameter of boring, on cutting performance are also examined. A method to improve the cutting performance is proposed based on the results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.1
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• pp.52-62
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• 2013

In order to obtain the relation between the cutting force and the process parameters in the chamfering process for the gear of a gear shaft, analysis of the process was performed with a simplified model instead of considering the whole actual 3-dimensional cutting situation produced between cutting tool and gear. The model divided the actual situation into the accumulation of hundreds of 2-dimensional layers with a small thickness in the direction of the height of gear and derived cutting force at a cutting position by accumulating each cutting force calculated in a layer. With proposed method to analyze the cutting forces in the chamfering process, it was revealed that the cutting position and size were exactly searched to calculate the cutting force in each layer. The total cutting force was the highest in the corner where the cutter encountered the gear first during the relative motion between them. The cutting forces were changed in proportion to the cutting parameters such as feed rate and trajectory.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.4
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• pp.34-43
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• 2002

The purpose of this paper is to further extend the theoretical understanding of the dynamic end milling process and to derive a computational model to predict the milling force components. A comparative assessment of different cutting force models is performed to demonstrate that the instantaneous shear plane based formulation is physically sound and offers the best agreement with experimental results. The procedure f3r the calculation of the model parameters used in the cutting force model, based on experimental data, has been presented. The validity of the proposed computational model has been experimentally verified through a series of cutting tests.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.788-793
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• 1997

The surface,generated by end milling operation, is deteriorated by tool runout,vibration,friction,tool deflection, etc. In many source,deflection of tool affects to surfave accuracy. To develop a surface accracy model,method for the prediction of the topography of machined surfaces has been developed based on models of machine tool kinematics and cutting tool geometry. This model accounts for not only the ideal geometrical surface, but also the deflection of tool resulted in cutting force. For the more accurate prediction of cutting force,flexible end mill model is used to simulate cutting process. Compute simu;ation have shown the feasibility of the surface generation system.