• 대한기계학회논문집A
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• 제20권1호
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• pp.222-231
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• 1996

Temperature distribution on the flank face in orthogonal turning with cutting tool of high speed steel is studied by using a finite element method and experiments. Experiments are carried out to verify the validity of the temperature measurement by using a thermoelectric couple junciton imbedded in a cutting tool of high speed steel. Good agreement is obtained between the analytical results and the experimental ones for the temperature distributions on flank face of cutting tool with igh speed steel. The analytical results show that the temperature on the top flank face of a tool is higher because of the difference of the friction velocity on each face of the tool.

• 대한기계학회논문집
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• 제18권12호
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• pp.3195-3201
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• 1994

In order to analytically predict tapping torque and thrust force in high speed tapping, a cutting model for main cutting edge with a uniformly restricted tool-chip contact area were developed. From this model equations are derived for the prediction of tapping torque given the cutting conditions, tap geometry, and an empirical factor which is related to the workmaterial. Computed values of torque is shown to compare favorably with those obtained from tapping tests on 16MnCr5. The applied torque about the cutting edge of teeth at lead chamfer is estimated respectively and it is shown that observed value is gradually decreased with following teeth.

• 한국생산제조학회지
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• 제8권2호
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• pp.137-143
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• 1999

The study of the high speed machining of inclined plane using ball end mill is performed. The use of ball end mill is rapidly growing in die and mold manufacturing. The cutting characteristics, such as cuttin g force, surface roughness and surface profile, are varied according to the variation of cutting directions. Free surface is cut using ball end mill, the surface profile is greatly varied depending upon the cutting direction. So this study will deal with the characteristics of cutting such as cutting efficiency according to the inclined plane of the workpiece, the cutting force according to tool path, surface profile and the roughness of surface. The optimal cutting direction to be applied the cutting for 3-D sculptured surfaces can be show through the results of this study.

• 한국기계가공학회지
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• 제1권1호
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• pp.38-47
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• 2002

Machining quality has been improved with the development of cutting tools. However, it is difficult to obtain a high degree of quality in machining a deep pocket with a long end mill, since machining accuracy is mainly dependent on the stiffness of the cutting tool and tool holder. To improve machining quality in machining a deep pocket using an end mill, the performance by cutting condition compare with others. Owing to this problem, it is necessary to select suitable tool and holder in the deep pocket machining. In this study, the hydraulic holder for the high speed machining is introduced and the performance of that is compared with others according to cutting conditions. The cutting parameters involved were; slenderness ratio in the range of 3 to 6 (L/D), radial depth of cut from 0.01 to 0.05 mm. Cutting force and surface roughness, precision of form were observed during the experiment to investigate cutting state.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.67-72
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• 1994

Tool test was conducted to investigate the were process of only flank face TiN coated HSS tool in interrupted cutting for variuos cutting speeds and feed rates. Flank wear was caused by microchipping at the cutting edge. At high cutting speed, the which was formed as a result of diffusion and abrasion lowered cutting edge and influenced flank were. Flank wear due to chipping was little influenced by cutting speed.

• Journal of the Korean Wood Science and Technology
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• 제16권4호
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• pp.61-69
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• 1988

Recently the automization of wood manufacturing and the development of CNC machine tools becomes the center of interest. Cutting mechanism, tool wear and the roughness of machined surface have been studied. In the studies about wood for special uses, concrete data of cutting is desired. While Pinus densiflora is characterized that heartwood develops as age increases, Chunyang District has the characteristic of strength, red color, relatively regular chap and high heartwood - percentage. But there is no data about cutting this wood, Chunyang District. In this study face milling by sintered carbide tool was excuted to Chunyang District. Cutting force, Surface roughness and states were investigated with regard to cutting speed. Example results were as follows; 1) Mean cutting resistance against lateral component force and longitudinal component force decreased rapidly up to cutting speed of 155 m/min, and remains constant above this speed. 2) The surface roughness of cutting surface lowered as cutting speed increased, regardless of fiber formation. Radial rougness of fiber is larger than lineal surface roughness. 3) Increase in Cutting speed made machining mark restrained. Down-milling showed larger marks than up-milling.

• 한국정밀공학회지
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• 제21권1호
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• pp.133-139
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• 2004

High speed machining (HSM) can reduce machining time with the high metal removal rate by high speed spindle and feedrate. This paper supports HSM technology using the small size tool with the optimal tool path generation and modification of tool change. The optimum tool path is generated to reduce cutting length of cavity pattern and change the cutting tool for preventing the tool breakage by wear. The tool path is modified with the experiment data of tool wear and breakage to support tool change on reasonable time. The result can contribute to HSM technology of high hardness materials using the small size end-mill.

• 한국정밀공학회지
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• 제17권5호
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• pp.186-194
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• 2000

The purpose of this study is to investigate the difference in cutting characteristics of cermet, carbide and coated carbide tools in the similar application range via turning test of various conditions. The cermet and carbide tools in the range of ISO P10 grade were developed using optimum compositions with a view to obtaining a high toughness and hardness by PM process. First mechanical properties were characterized on these tools. Experimental results of wear behaviour and resistance to fracturing were presented and discussed in the turning of gray cast iron and alloy steels by cermet, carbide and coated carbide tools. The coated carbide tool shows similar cutting performance compared to the cermet, while the cermet has better combination of wear resistance and toughness of high speed (V=500m/min) cutting in comparison with carbide and coated carbide tools, and also shows a potentiality for cast iron cutting. Fe adhesive behaviour on the tools and surface roughness of workpieces were explained by chemical affinity between tools and workpieces.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 추계학술대회 논문집
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• pp.141-146
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• 2002

Real-time monitoring and control of the cutting force is essential for unmanned cutting process. Although the cutting force can be measured directly using tool dynamometers, their implementation is not feasible in industry due to high cost. Alternative approach is the cutting force estimation based on spindle drive models, but it requires the knowledge of their characteristics with the spindle speed variation. This paper investigates the power-factor and frictional characteristics of three-phase induction motors and determines its characteristics below and above the base speed, respectively. In order to realize the proposed cutting force monitoring system, a stand-alone DSP board was utilized. Its monitoring and control performance is evaluated in a CNC lathe.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.41-45
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• 1996

In order to realize the high-speed machining, the relative technologies for high speed machining tool and high speed machining are required now, The machining accuracy is influenced on the disturbance by the synchronized working conditions(cutting force, spindle Run-out, thermal deformation etc.) In this paper, the effect of spindle Run-out for the high speed machining is investigated. The results show that the spindle Run-out has a great influence on the machining accuracy in high speed machining.