• 한국기계가공학회지
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• 제3권1호
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• pp.22-27
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• 2004

Recently, environmental pollution has become a significant problem in industry and many researchers have investigated in order to preserve the environment. Environmentally conscious machining and technology have more important position in machining process, because cutting fluid has bad influence on the environment in milling process. This research is the experimental study on high speed machining of aluminum alloys through environmentally conscious machining. In this study, the surface roughness and chip appearance was investigated in the machining of aluminum alloys by dry machining, using cutting fluid and oil mist.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.822-826
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• 1997

근래에 들어, 금형생산 시간의 단축과 고정밀도의 제품을 생산하기 위해 실가공전의 설계단계에서 금형 데이터를 수치적으로 검증할 필요가 높아지고 있다. 기존의 저가형 CAM시스템에서 사용된 경로표시법으 로는 이러한 검증이 불가능하기 때문에 새로운 방법의 도입이 필요하며 모의가공 형상의 표현에서도 비매 개변수형 곡면을 이영하는 방법이 널리 사용되고 있다. 본 연구는 3축 금형가곡에 사용되는 볼앤드밀, 평 엔드밀 공구에 대해 Z-map을 기반으로 절삭부위를 비매개변수형 곡면으로 모델링하여 모의가공을 수행하 고자 한다. 또한, 새로운 backeting영역지정 방법을 사용하여 모의가공의 효율을 높였다.

• 한국기계가공학회지
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• 제18권11호
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• pp.89-95
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• 2019

In this research, the effect of roughing on tool load through bottom-up machining is investigated through actual machining. Generally, through the use of high-speed machining technology, machining methods, such as general roughing, operate by deepening the cutting depth for as long as the tool is able to withstand it, giving a slower feed rate, less cutting depth, and faster feed. However, when the cutting depth is deep, there is a problem in that the stepped shape of the cutting area is increased (e.g., by the shaking of the tool or the chipping load). However, if the cutting is performed less, the cutting time becomes relatively long. To compensate for these drawbacks and extend the service life of the tool, economic efficiency needs to be secured.

• 한국기계가공학회지
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• 제10권5호
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• pp.20-25
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• 2011

In this paper, we reviewed the spindle system's motor and bearing and its mode safety for optimal design of a high speed spindle system that exceeds DmN value of 1,500,000. We could verify that it has a separation margin during critical speed by performing critical speed analysis. Also, we have selected an optimal sensoring installation location and actually manufactured & installed the sensor by identifying the stress concentration position in the axial load through finite element analysis to install the built-in piezo electric type load sensor to the spindle housing that can measure and monitor the machining load during high speed rotation of the spindle. Reproducibility is also verified by calibrating the error through the sensor's sensitivity adjustment after comparing the output between the plate dynamoneters and the load sensor to confirm the reproducibility of the load sensor.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.343-348
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• 2000

The term‘High Speed Machining’has been used for many years to describe end milling with small diameter tools at high rotational speeds. typically 10,000 - 100,000 rpm. The process was applied in the aerospace industry for the machining of light alloys, notably aluminium. In recent years, however, the mold and die industry has begun to use the technology for the production of components, including those manufactured from hardened tool steels. And the end-mill is an important tool in the milling process. A typical examples for the end mill is the milling of pocket and slot in which a lot of material is removed from the workpiece. Therefore the proper selection of cutting parameters for end milling is one of the important factors affecting the cutting cost. The one of the advantages of HSM is cutting thin-wall part of light alloy like Al (thinkness about 0.3mm). In this paper, firstly, we study characteristics of HSM, and then, we choose the optimal parameters(cutting forces) and investigate various machining strategies to cut thin-wall part by experiment.

• 한국정밀공학회지
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• 제16권5호통권98호
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• pp.11-18
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• 1999

Recently high speed machining is being studied actively to reduce machining time and to improve machining precision. To perform efficient high speed machining, evaluation of high speed machinability must be studied preferentially and it can be identified by investigation of cutting force. To measure cutting forces in high speed machining, dynamometer which has high natural frequency was newly designed using 3-axes piezo force sensor. For newly designed dynamometer, calibration is conducted with sensitivity of force sensor modulated and proper preload and interference force are investigated experimently. Also, cutting force signals of newly designed dynamometer are compared with those of conventional one in high speed cutting experiment and its superiority is confirmed. Then using newly designed dynamometer, high speed machinability is evaluated about cutting force and tool wear in various cutting conditions.

• 한국기계가공학회지
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• 제5권4호
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• pp.59-64
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• 2006

High Speed Machining(HSM) reduces machining time and improves surface accuracy because of the high cutting speed and feedrate. Development of HSM makes it allowable to machine difficult-to-cut material and use small-size-endmill. It is however limited to cutting condition and tool material. In the machining operation, it is important to check main parameter of tool life and select optimal cutting condition because tool breakage can interrupt progression of operation. In this study, cutting parameters are determined to 3 factors and 3 levels which are a spindle speed, a feedrate and a width of cut. Experiment is designed to orthogonal array table for L9 with 3 outer array using Taguchi method. Also, it is proposed to inspect significance of the optimal factors and levels by ANOVA using average of SN ratio for tool life. Finally, estimated value of SN ratio in the optimal cutting condition is compared with measured one in the floor shop and reduction of loss is predicted.

• 한국기계가공학회지
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• 제9권1호
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• pp.81-86
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• 2010

This paper investigated into process characteristics of AlTiN coated layers for machining to the direction of upper and lower in plastic mold material (KP-4) with the cemented carbide ball endmill with the diameter of 8mm coated AlTiN layers (1~4) step by step using machining center. The material used in experiments was KP-4 that was machined by three types of inclined angles; $15^{\circ}$, $30^{\circ}$ and $45^{\circ}$ As estimated mechanical properties of AlTiN coated layers, it was shown the most result in the condition of three layered coating that the coating that the coating depth, the hardness of the coated layer and the surface roughness of the coated layer were $13{\mu}m$, Hv 3027.3 and $0.042{\mu}m$, respectively. The cutting component was better at the condition of upper direction than that of lower direction in all experimental conditions and indicated to be less which the bigger angle of the material was increased the effective diameter of the tool.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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• pp.83-88
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• 2001

In order to suggest the proper optimal conditions of the CNC milling machining for the Thin-wall surface, some experiments were carried out. The process was applied in the aerospace industry for the machining of light alloys, notably aluminium. In recent year, however, the mold and die industry has begun to use the technology for the production of components, including those manufactured from hardened tool steels. And the end mill is an important tool in the milling process. A typical example for the end mill is the milling of pocket and slot in which a lot of material is removed from the workpiece. Therefore the proper selection of cutting parameter for end milling is one of the important factors affecting the cutting cost. In this paper, we choose the optimal parameters(cutting forces) to cut thin-walled Al part by experiment.

• 한국공작기계학회논문집
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• 제15권6호
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• pp.50-57
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• 2006

The investigation of microscopic precision in high speed endmilling is necessary for machinability evaluation, and the environmentally conscious machining technology have more important position in recent machining process. The microscopic precision of workpiece is influenced by machining environments variation as cutting fluid type and lubricant method. In this study, the cutting forces according to variation of cooling and lubrication are investigated by specially designed tool dynamometer. And the surface roughness, micro hardness and residual stress are evaluated according to machining environment. The characteristics of damaged layer in environmentally conscious machining and conventional machining using cutting fluid are compared experimentally.