• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.281-281
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• 2011

산업 환경에서 친환경 및 에너지효율성을 중요한 조건이 되면서 고효율성 및 다기능을 가진 재료에 대한 연구가 활발히 진행 되고 있다. 특히 Al-Ti-N 코팅은 이미 경도 측면에서 우수 하여 고속 공구 부품에 널리 사용되고 있고 최근에 Al-TiN에서 Si 첨가는 40GPa이상의 고경도와 1000도 이상의 산화온도를 지닌 나노 혼합물 코팅을 형성 시키는 것으로 알려져 있다. 본 연구에서 Al-Ti에 Si, Cu, Cr 을 첨가하였을 때 코팅을 형성하였을 때 바뀌는 물성 변화을 확인하였다. 이러한 연구를 위해 Al-Ti 합금 조성 중 가장 우수한 것으로 알려진 60:40으로 타겟을 만들어 스퍼터 장비를 이용해 코팅을 형성하여 기초 실험을 진행하였다. 그 근거로 하여 3원계인 Si, Cu, Cr 을 첨가하여 각각의 단일 타겟으로 만들고 코팅을 형성하였다. 타겟과 코팅의 성분이 동일한지 확인하기 위해 EPMA분석을 하였고 그 결과 오차 범위 내에 동일한 것으로 확인하였다. 또 내산화성 테스트를 위해 400도에서 1000도로 가열된 대기 중에 코팅 층을 1시간씩 노출시키는 공정을 통해 확인하였고 내식성 테스트는 SUS 304계열 위에 코팅을 하여 Potentiodynamic polarization scan 장비로 비교해 보았다. 표면경도는 3원계 코팅인 경우 질소비율이 증가할수록 30GPa ~ 35GPa까지 증가하였고 XRD 분석 결과와 비교 시 (111), (200) peak가 명확할수록 경도 값이 높은 것으로 확인하였다. 마모테스트 결과 3원계인 코팅 층이 dry상태에서 감소하는 경향을 보였다. 특히 0,26까지 감소한 Si 을 첨가한 코팅 층은 H/E지수도 좋아 마모트랙의 길이도 짧아 우수한 것으로 알 수 있었다. 이런 결과에서 보듯 3원소 이상 첨가 시 특성변화가 차이가 있다는 것을 알 수 있었다.

• 열처리공학회지
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• 제22권5호
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• pp.307-311
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• 2009

In this study, TiCrN films were deposited on STS 316 Land Si (100) wafer by inductively coupled plasma (ICP) assisted D.C. magnetron sputtering. The effect R.F. power for ICP discharge on the mechanical properties of TiCrN films was investigated. XRD, XPS and FE-SEM were used for the structure analysis. Also the Micro-Knoop hardness tester and profilometer were used for measuring hardness of coatings and film stress respectively. As increasing the R.F. power for ICP discharge, thickness of coating was decreased from 1633 nm to 1288 nm but hardness was increased about $Hk_{5g}$ 4200 at 400 W. All of the XRD patterns showed (111), (200) and (220) peaks of TiCrN films. Surface morphology was studied using the profilometer. FE-SEM was used to know morphology and cross-section of the films. Structure of the films was changed dense as increased ICP power.

• 한국재료학회지
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• 제31권6호
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• pp.331-338
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• 2021

Ti-Al-Si target and Cr-Si target are sputtered alternately to develop a multi-layered nitride coating on a steel mold to improve die-casting lifetime. Prior to the multi-layer deposition, a CrN layer is developed as a buffer layer on the mold to suppress the diffusion of reactive elements and enhance the cohesive strength of the multi-layer deposition. Approximately 50 nm CrSiN and TiAlSiN layers are deposited layer by layer, and form about three ㎛-thickness of multi-layered coating. From the observation of the uncoated and coated steel molds after the acceleration experiment of liquid metal injection casting, the uncoated mold is severely eroded by the adhesion of molten metallic glass. On the other hand, the multi-layer coating on the mold prevents element diffusion from the metallic glass and mold erosion during the experiment. The multi-layer structure of the coating transforms the nano-composite structured coating during the acceleration test. Since the nano-composite structure disrupts element diffusion to molten metallic glass, despite microstructure changes, the coating is not eroded by the 1,050 ℃ molten metallic glass.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2006년도 춘계학술발표회 초록집
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• pp.153-153
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• 2006

• 한국정밀공학회지
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• 제31권6호
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• pp.513-519
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• 2014

For depth machining in die and mold, Electrical Discharge Machining (EDM) is used generally. To make deep hole and deep shape efficiently, cemented carbide endmill for depth machining is necessary. For this purpose, cemented carbide endmill was designed using design of experiment (DOE). To improve cutting performance, endmill was coated with multilayer surface treatment, TiAlCrSiN and TiAlCrN, for higher wear resistance. In order to evaluate the endmill, Transverse Rupture Strength (TRS) test was tried for investigating the relationship between surface treatment and strength in endmill body. Scratch test was also used for measuring adhesion force of each surface treatment. To evaluate hardness of surface treatment, Atomic Force Microscope (AFM) analysis was carried out. Wear test was executed for characteristics of each surface treatment in high temperature. Consequently, TiAlCrSiN was superior to the TiAlCrN coating in case of high temperature environment such as cutting.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2013년도 춘계학술대회 논문집
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• pp.206-206
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• 2013

산악자전거 서스펜션 포크 프레임의 소재 개발을 위해 Si, Mn, Mg, Cr, Zn 원소의 첨가량을 조정한 500MPa 인장강도를 가지는 압출성형과 용접성이 우수한 알루미늄 합금을 개발하였다. 개발한 고비강도 경량 알루미늄합금 위에 고경도, 고기능성과 같은 우수한 기계적 물성을 가진 TiN 박막을 Arc ion plating 공정으로 코팅하여 알루미늄합금의 내부식성, 내구성을 향상시켰다.

• 한국표면공학회지
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• 제34권5호
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• pp.421-428
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• 2001

New WC-CrN superlattice film was deposited on Si substrate (500$\mu\textrm{m}$) using cathodic arc ion plating system. The microstructure and mechanical properties of the film depend on the superlattice period (λ). In the X-ray diffraction analysis (XRD), preferred orientation of microstructure was changed according to various superlattice periods(λ). During the Transmission Electron Microscope analysis (TEM), microstructure and superlattice period (λ) of the WC - CrN superlattice film was confirmed. Hardness and adhesion of the deposited film was evaluated by nanoindentation test and scratch test, respectively. As a result of nanoindentation test, the hardness of WC - CrN superlattice film was gained about 40GPa at superlattice period (λ) with 7nm. Also residual stress with various superlattice period (λ) was measured on Si wafer (100$\mu\textrm{m}$) by conventional beam-bending technique. The residual stress of the film was reduced to a value of 0.2 GPa by introducing Ti - WC buffer layers periodically with a thickness ratio ($t_{buffer}$/$t_{buffer+superlattice}$ ). To the end, for the evaluation of oxidation resistance at the elevated temperature, CrN single layer and WC - CrN superlattice films with various superlattice periods on SKD61 substrate was measured and compared with the oxidation resistance.

• Transactions on Electrical and Electronic Materials
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• 제4권1호
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• pp.15-20
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• 2003

NiCr alloys are prepared onto poly-Si/ $SiO_2$/Si substrates to replace Pt bottom electrode with a new one for integration of high dielectric constant materials. Alloys deposited at Ni and Cr power of 40 and 40 W showed optimum properties in the composition of N $i_{1.6}$C $r_{1.0}$. The grain size of films increases with increasing deposition temperature. The films deposited at 50$0^{\circ}C$ showed a severe agglomeration due to homogeneous nucleation. The NiCr alloys from the rms roughness and resistivity data showed a thermal stability independent of increasing annealing temperature. The 80 nm thick BST films deposited onto N $i_{1.6}$C $r_{1.0}$/poly-Si showed a dielectric constant of 280 and a dissipation factor of about 5 % at 100 kHz. The leakage current density of as-deposited BST films was about 5$\times$10$^{-7}$ A/$\textrm{cm}^2$ at an applied voltage of 1 V. The NiCr alloys are possible to replace Pt bottom electrode with new one to integrate f3r high dielectric constant materials.terials.

• 한국결정성장학회지
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• 제23권4호
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• pp.161-166
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• 2013

실리콘 기판 위에 GaN를 성장하기 위해서 AlN 완충층을 사용해 왔다. 그러나 AlN은 아직까지 high doping이 쉽지 않기 때문에, 이로 인해 AlN를 전자소자나 광소자 제작을 위한 완충층으로 이용하는 경우 직렬 저항의 증가라는 문제가 발생할 수 있다. 본 연구에서는 이러한 문제점을 개선하기 위해 AlN 완충층 대신에 금속 완충층을 사용하여 실리콘 기판 위에 GaN 박막 성장실험을 수행하였다. Al, Ti, Cr 그리고 Au 등을 금속 완충층으로 사용하여 실리콘 기판 위에 GaN 층을 성장하였다. 성장된 GaN 박막의 표면 특성을 분석하기 위해 광학현미경과 SEM을 사용하였고, 결정성과 광학적 특성을 평가하기 위하여 PL과 XRD 분석을 실시하였으며 AlN 완충층을 사용한 경우와 금속 완충층을 사용한 경우의 저항 차이를 확인하기 위하여 전류-전압 특성을 측정하였다.

• 한국표면공학회지
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• 제54권3호
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• pp.133-138
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• 2021

Ternary Ti-X-N coatings, where X = Al, Si, Cr, O, etc., have been widely used for machining tools and cutting tools such as inserts, end-mills, and etc. Ti-Al-N-O coatings were deposited onto silicon wafer and WC-Co substrates by a cathodic arc evaporation (CAE) technique at various negative substrate bias voltages. In this study, the influence of substrate bias voltages during deposition on the microstructure and mechanical properties of Ti-Al-N-O coatings were systematically investigated to optimize the CAE deposition condition. Based on results from various analyses, the Ti-Al-N-O coatings prepared at substrate bias voltage of -80 V in the process exhibited excellent mechanical properties with a higher compressive residual stress. The Ti-Al-N-O (-80 V) coating exhibited the highest hardness around 30 GPa and elastic modulus around 303 GPa. The improvement of mechanical properties with optimized bias voltage of -80 V can be explained with the diminution of macroparticles, film densification and residual stress induced by ion bombardment effect. However, the increasing bias voltage above -80 V caused reduction in film deposition rate in the Ti-Al-N-O coatings due to re-sputtering and ion bombardment phenomenon.