• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 추계학술대회논문집
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• pp.19-22
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• 2004

Shearing including punching, blanking, trimming, slitting, etc is one of the most frequently used processes in sheet metal manufacturing. It has been widely using for manufacturing autobody, electronic components, aircraftbody, etc. In this paper, it has been researched by the experimental investigation to examine the influence of shearing processes parameters such as clearance, cutting angle, material properties, etc. From the results of experiment, it has shown that it gives the small variations at burr height below the proper clearance and it also presents that it is no affected the variations of cutting angle.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.638-639
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• 2006

Multilayered coatings on tungsten carbide cutting tools are widely used for enhancing cutting performance. In this paper, we review the CVD TiC/TiCN multilayer as a function of the multilayer period. The TiC/TiCN multilayers in initial stage show preferred (220) orientation but shifts to (200) orientation with decreasing multilayer period. The nanohardness of TiC/TiCN multilayers were found to increase with decreasing multilayer period and shows a maximum of 23.8 GPa at a period = 33.5 nm.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 춘계학술대회 논문집
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• pp.379-380
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• 2008

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.507-512
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• 2001

In this work, tool holder system has been designed and builted to measure cutting forces in diamond turning. This system design includes a 3-component piezo-electric tranducer. Initial experiments with tool holder system included verification of its predicted dynamic characteristics as well as a detailed study of cutting parameters. Tool holder system is modeled by considering the element dividing, material properties, and boundary conditions using MSC/PATRAN. Mode and frequency analysis of structure is simulated by MSC/NASTRAN, for the purpose of developing the effective design. Many cutting experiments have been conducted on 6061-T6 aluminum. Tests have involved investigation of velocity effects, and the effects of depth and feedrate on tool force. Forces generally increase with increasing depth of cut. Increasing feedrate does not necessarily lead to higher forces.

• 한국정밀공학회지
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• 제30권5호
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• pp.537-543
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• 2013

In this paper, a novel radial beam coupling model was proposed and the design parameters were studied for the efficient transmission of torque. To develop a high performance radial beam coupling, an analytical way to predict the performance in design phase is required. One of the best ways to estimate the performance of the coupling without manufacturing is to evaluate the stress and torsional stiffness by building a finite element model with a special attention to the radial beam cutting part. For the best results of FEA, the material properties were obtained through testing. To verify the reliability of finite element model, the results of FEA were compared with the experiments. The main design parameters of radial beam cutting width, radial beam cutting depth, and radial beam cutting direction were considered for the performance of radial beam coupling.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1597-1600
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• 2005

Recently, the trends of TFT-LCD are large scale and thin thickness, so, the demands of Light Guide Panel(LGP) which is able to substitute for prism sheets are appeared. Functions of LGP obtaining polarization of light of the prism sheet as well as the incidence and reflection of light are demanded. This prismless type LGP to complete functions of the existing LGP and polarization at once must be supported by micro machining technology of LGP surface. In this research, we have used the STAMPER method for the mass product and In-Line process, and the optimized conditions are established by analyzing the cutting force and conditions according to the material and processing properties when the prismless type LGP mold is fabricated. Parameters of the cutting condition were the workpiece and cutting depth.

• 한국분말재료학회지
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• 제22권3호
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• pp.169-174
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• 2015

The optical film for light luminance improvement of BLU that is used in LCD/LED and retro-reflective film is used as luminous sign consist of square and triangular pyramid structure pattern based on V-shape micro prism pattern. In this study, we analyzed machining characteristics of Cu-plated flat mold by shaping with diamond tool. First, cutting conditions were optimizing as V-groove machining for the experiment of micro prism structure mold machining with prism pattern shape, cutting force and roughness. Second, the micro prism structure such as square and triangular pyramid pattern were machined by cross machining method with optimizing cutting conditions. Burr and chip shape were discussed with material properties and machining method.

• 터널과지하공간
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• 제13권6호
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• pp.413-420
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• 2003

본 논문에서는 터널 및 지하공간의 기계화 시공에 있어서 굴진성능을 예측하는 모델링 기법을 고찰하였다. 첫 번째로 세계적으로 가장 잘 알려져 있는 두 가지 모델, 즉 이론적 접근을 기본으로 하고 있는 CSM 모델과 경험적 접근을 기본으로 하고 있는 NTH 모델의 비교를 수행하였다. 두 번째로는, 특별히 Constant Cross Section 커터를 사용하는 경우의 암석 굴삭 원리를 알아보고, 이 원리를 기본으로 하는 이론적 모델을 전개하여 암석특성과 커터 제원만으로 유도되는 절삭력을 구하는 관계식을 고찰하였다. 세 번째로는 기계화 시공에 있어서 굴진성능을 예측하기 위한 일반적인 모델링 기법을 제시하였다. 마지막으로 미국 Colorado School of Mines의 Earth Mechanics Institute(EMI)에서 개발한 CSM 컴퓨터 모델을 소개하고, 이 모델을 TBM 설계에 적용한 사례를 제시하였다.

• 콘크리트학회지
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• 제2권1호
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• pp.79-90
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• 1990

철근 콘크리트 보의 인장철근이 합리적인 위치에서 체단(Cutoff)되지 않으며, 응력집중 및 부재의 극한강도가 저하되는 등의 문제가 발생될 수 있다. 따라서, 본 연구에서는 이러한 상황에 부합되는 실제건물을 대상으로 실물크기(Full Scale) 및 모형 실험을 함으로써 체단점에서 발생되는 파괴양상과 휨 강도, 실물, 시험체와 모형 시험체의 파괴 진전 상황등을 비교\ulcorner분석하고, 동시에 유한요소법에 의한 해석을 통하여 인장응력 분포 상태등을 검토함으로써 보 설계시 인장철근의 체단등에 관한 기토자료를 제공하고자 하였다. 실험 및 해석의 결과로부터, 체단부가 지점쪽으로 멀리 있을수록 최대내력의 감소는 물론 인장응력의 집중현상등이 나타나고 있는 바, 보부재의 설계시 인장철의 체단보에 대해서는 세심한 주의가 필여하리라 사료된다.

• 한국기계가공학회지
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• 제17권4호
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• pp.1-8
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• 2018

In drilling Inconel 601, which is used for compressor cases in aircraft engines, a lot of cutting oil must be supplied. This prevents tools from wear and fracture due to the heat buildup resulting from the high-temperature resistance and toughness of this alloy. However, the cutting oil supply has compromised the machining environment. This has caused attention to shift to an environmentally friendly cutting fluid supply system called the Minimum Quantity Lubrication(MQL) system. The aim of this study was to find a more efficient drill processing method using MQL and to verify its performance. To that end, the properties of Inconel that make it difficult -to -drill were studied by a comparison with the drilling of SM45C. Specific factors (i.e., cutting force and tool wear) were examined in relation to the conditions in the MQL-based drilling system. Based on these results, a sealed cover and step feed were proposed as measures to increase the effectiveness of the MQL system. The efficiency of the proposed method was established.