• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1992년도 추계학술대회 논문집
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• pp.17-21
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• 1992

최근 들어 공작기계 자동화의 보편화로 절삭가공작업은 고속화, 정밀화되고 있어 생산성을 높이고 있다. 하지만 이러한 생산성의 증가는 단위시간당 chip생산량을 증가시켰으며, 이에 따라 효율적이면서 바람직한 chip처리가 생산성 향상과 연관되어 매우 중요한 문제로 대두되었다. 본 연구에서는 부착장애형 chip breaker를 설치한 insert 공구를 이용, 피삭재로서 내식성, 내마모성을 기계적 성질이 우수하여 근래 산업의 여러 분야에서 각광받고 있는 난삭재 STS304를 절삭하였다. 난삭재 STS304연질금속으로서, 자유표면이 다소 매끄러운 일반재료와 달리 chip의 단면이 어느 정도 규칙적인 톱니형 chip을 발생한다. 그러므로 부착장애형 chip breaker의 각 및 거리, 기타 각 조건을 이용하여 STS304를 절삭특성 및 chip 조절상태를 관찰하고, 기존의 실험에서 자주 이용되었던 연강과 STS304의 비교절삭을 행하여 chip형태등을 비교하여 보는 것도 난삭재의 절삭가공기술 진전에 일조하리라 생각한다.

• 한국정밀공학회지
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• 제16권8호
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• pp.170-177
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• 1999

과공정 알루미늄 실리콘 합금 (Hypereutectic Al-Si Alloy, A390)은 내마멸성 및 우수한 강성에 의해서 자동차 부품에 많이 사용되고 있다. 본 연구에서는 초음파 진동 절삭에 의한 과공정 알루미늄 실리콘 합금의 가공성과 실리콘 석출의 실험적 연구를 수행 하였다. 최적 공구와 가공조건의 선정 실험을 통하여 보다 효과적인 초음파 진동 절삭을 수행하였으며, 과공정 알루미늄 실리콘 합금의 가공 표면거칠기와 실리콘 석출은 절삭속도와 절삭깊이와 밀접한 연관성을 갖고 있다.

• 한국정밀공학회지
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• 제22권5호
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• pp.167-174
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• 2005

High-speed machining is one of the most effective technologies to improve productivity Because of the high speed and high feed rate, high-speed machining can give great advantages for the machining of dies and molds. This paper describes on the analysis and evaluation of cutting force in high-speed machining. Cutter rotation directions, slope directions, spindle revolution and depth of cut are control factors for cutting force. The effect of the control factors on cutting force is investigated for the high speed machining of STD11.

• 대한의용생체공학회:의공학회지
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• 제20권2호
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• pp.231-236
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• 1999

Q-switch된 Er:YAG 레이저를 이용해서 치아표면에 뿜어준 외부의 물로 인해 유도된 열 및 역학적인 효과를 이해하는 것은 free-running Er:YAG 레이저에 의한 절삭효과를 이해하는데 대단히 중요하다. 이는 (파장 하나의 길이가 250 $\mu\textrm{s}$인) free-running 레이저에 의한 한 거 대효과가 본 실험에서 이용한 (파장 하나의 길이가 1 $\mu\textrm{s}$인) Q-switch된 레이저에 의한 미소효과들의 축적이기 때문이다. 치아표면에 물이 있을 때 Q-Switch된 레이저에 의한 절삭률은 그렇치 않은 때에 비해 증가되었다. 치아표면에 물을 뿜어주는 횟수는 절삭률에 영향을 미쳐서 저에너지에서는 더디게 물을 뿜어줄때 놀은 절삭률을 얻었다. 반동압력의 세기는 치아표면 조건에 의존하는데. 표면이 젖을수록 그리고 뿜어준 물의 양이 증가 할 수록, 반동압력의 세기 또한 증가하였다. 이 연구로부터 우리는 1-$\mu\textrm{s}$-길이의 pulsed 레이저에 의해 유도된 열 및 역학적인 효과가 외부에 물이 있을 때 free-running Er:YAG 레이저에 의한 절삭을 이해하는데 중요한 정보를 제공해 준다는 것을 알았다.

• 한국자동차공학회논문집
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• 제21권5호
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• pp.74-81
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• 2013

The high-speed machining in the manufacturing industry field has been widely applied for parts of vehicles, aircraft, ships, electronics, etc., recently, because the effect of cost savings for shortening processing time and improving productivity is great. The purpose in this study is to investigate the effect of cutting depth on the surface roughness of workpiece with the spindle rotational speed and feed rate of high-speed machines as a parameter to find the optimal depth in the finishing for ball end mill of the aluminum alloy 7075 which is used much in aircraft parts. When the cutting depth for the respective feed rate and spindle rotational speed is varied from 0.1 mm to 0.7 mm at intervals of 0.2 mm in the wet finishing of the aluminum alloy 7075 by the insoluble cutting oils and high-speed machining used in the rough machining of previous study, the surface roughness values and the cutting temperature are measured. In addition, the cutting surface shapes of test specimens are observed by optical microscope and compared with respectively. It is found that the surface roughness values and the temperature generated during machining are increased as the feed rate and cutting depth are raised, but those are decreased as the spindle rotational speed is increased.

• 한국정밀공학회지
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• 제14권4호
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• pp.38-45
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• 1997

A new dynamic model for the cutting process inb the end milling process is developed. This model, which describes the dynamic response of the end mill, the chip load geometry including tool runout, the dependence of the cutting forces on the chip load, is used to predict the dynamic cutting force during the end milling process. In order to predict accurately cutting forces and tool vibration, the model which uses instantaneous specific cutting force, inclueds both regenerative effect and penetration effect, The model is verified through comparisons of model predicted cutting force with measured cutting force obtained from machining experiments.

• 한국공작기계학회논문집
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• 제16권2호
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• pp.84-91
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• 2007

The radial error motion of a machine tool cutter/spindle system is critical to the dimensional accuracy of the parts to be machined. This paper presents an investigation into spindle run-out effects on cutting mark and surface roughness. We experimented the effects of spindle run-out on surface roughness in flat-end milling by cutting AL 7075 workpiece in various cutting conditions. In order to analyze the effects of run-out on the surface roughness, the spindle's radial error motions was measured by mounting a sphere target onto the spindle as a reference. From the experimental results, it was found that spindle un-out makes a directive effects on surface roughness in flat-end milling.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1996년도 추계학술대회 논문
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• pp.64-74
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• 1996

The meachanism for cutting epoxy resins specimens which were specially provided was experimentally investigated to obtain a fine surface finish. the specimens were cut the three-dimensional undrer dry conditions using a lathe. the relationship between the topography of the cut surface due to the change rate of temperature of the cutting condition using sintered carbides (P20, K10, KT150) was investigated. the main results obtained are as follows: 1) The change rate of temperature of the cutting edge is increased in nearly proportion ot cutting speed feed rate depth of cut. 2)The profile of surface roughness were regulated k10 but irregulated P20 KT150. 3) The surface roughness value decreased K10 rather than P20 KT150. 3) The surface roughness value decreased K10 rather than P20 KT 150.4)The cutting resistance increased thrust force rather than cutting force due to the visco-elastic material of epoxy resins.

• 한국기계가공학회지
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• 제17권1호
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• pp.57-62
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• 2018

In this report, Cutting of metals are basically existence of fundamentally important cutting method. It is necessary task for the advanced technical production which are need more precision and efficient to over an idealistic surface roughness. This study is resulted through cutting the row materials of SM45C, in the diluted solubility water type of cutting fluids twenty times and forty times as many as that water, by variable in the velocity, feed rate, depth of cut, comparing the examine under same cutting conditions.

• 한국기계가공학회지
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• 제20권10호
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• pp.9-18
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• 2021

The cutting force in a cutting simulation is determined by the cutting conditions, such as cutting speed, feed rate, and depth of cut. The cutting force changes, depending on the material and cutting conditions, and is affected by the heat generated during cutting. The physical properties for predicting the cutting force use constitutive equations as functions of the hardening term, rate-hardening term, and thermal-softening term. To accurately predict the thermal properties, it is necessary to accurately predict the thermal-softening coefficient. In this study, the thermal-softening coefficient was determined, and the cutting force was predicted, using the response-surface method with the cutting conditions and the thermal-softening coefficient as factors.