• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 추계학술대회
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• pp.89-94
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• 2003

Hard coatings are known to improve the performance of cutting tools in aggressive machining applications, such as high speed machining. New superhard Ti-Al-Si-W films, characterized by a nanocomposite nano-sized (Ti,Al,Si)N crystallites embedded in amorphous $Si_3 N_4$ matrix, could be successfully synthesized on WC-Co substrates by a hybrid coating system of arc ion plating(AIP) and sputtering method. The hardness of Ti-Al-Si-N film increased with incorporation of Si, and had the maximum value ~50 GPa at the Si content of 9 at.%, respectively. And the X-ray diffraction patterns of Ti-Al-Si-N films with various Si content is investigated. In this study, Ti-Al-Si-N coatings were applied to end-mill tools made of WC-Co material by a hybrid coating system. Cutting tests fir the high-hardened material (STD11,$H_R$)C62 and their performances in high speed cutting conditions were studied. Also, the tool wear and tool lift of Ti-Al-Si-N with various si(6, 9, 19) contents were measured.

• 한국전기전자재료학회논문지
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• 제29권1호
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• pp.40-43
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• 2016

Transparent color coating films were fabricated on a glass substrate by using sol-gel hybrid binder and organic dye. Sol-gel hybrid binder coating film fabricated with PTMS of 0.03 mole showed a very high pencil hardness of 9 H. As the withdrawal speed increased from 1.0 mm/s to 5.0 mm/sec, The yellowness ($b^*$) of coating glass also gradually increased. The transmittance of yellow color coating glass was 82.6% and the haze of coating glass was 0.35%. Red and blue color coating glasses also showed the high transmittance of 62.4% and 80.6% respectively. The surface hardness of color coating films was 6 H.

• 한국초전도ㆍ저온공학회논문지
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• 제15권2호
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• pp.9-11
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• 2013

We have investigated the effect of thickness of the MgB2 film on the grain growth direction as well as on their superconducting properties. $MgB_2$ films of various thicknesses were fabricated on c-cut $Al_2O_3$ substrates at a temperature of $540^{\circ}C$ by using hybrid physical-chemical vapor deposition (HPCVD) technique. The superconducting transition temperature ($T_c$) was found to increase with increase in the thickness of the $MgB_2$ film. X-ray diffraction analysis revealed that the orientation of grains changed from c-axis to a-axis upon increasing the thickness of the $MgB_2$ film from 0.6 to 2.0 ${\mu}m$. $MgB_2$ grains of various orientations were observed in the microstructures of the films examined by scanning electron microscopy. It is observed that at high magnetic fields the 2.0-${\mu}m$-thick film exhibit considerably larger critical current density ($J_c$) as compared to 0.6-${\mu}m$-thick film. The results are discussed in terms of an intrinsic-pinning in $MgB_2$ similarly as intrinsic-pinning occurring in high-Tc cuprate superconductors with layered structure.

• 대한금속재료학회지
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• 제50권8호
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• pp.549-556
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• 2012

The tribological behavior of CrMoN films with respect to surface chemistry was investigated by using X-ray photoelectron spectroscopy (XPS). All of the films were prepared from a hybrid PVD system consisting of DC unbalanced magnetron (UBM) sputtering and arc ion plating (AIP) sources. The tribological property of the films was evaluated by a friction coefficient using a Ball-on-disk type tribometer. The chemistry of wear track was analyzed by energy dispersive spectroscopy (EDS) and XPS. The friction coefficient was measured to be 0.4 for the CrMoN film, which is lower than that of a monolithic CrN film. EDS and XPS results imply the formation of an oxide layer on the coating surface, which was identified as molybdenum oxide phases, known to be a solid lubricant during the wear test.

• Korean Chemical Engineering Research
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• 제50권4호
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• pp.632-638
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• 2012

Isophorone diisocyanate (IPDI), polycarbonate diol (PCD), dimethylol propionic acid (DMPA)를 출발물질로 하여 수분산 폴리우레탄(waterborne polyurethane dispersion, PUD)을 합성하였다. 이 PUD에 아크릴 단량체인 HEMA (2-hydroxyethyl methacrylate)와 MMA (methyl methacrylate)의 혼합물을 첨가하여 수분산 폴리우레탄-아크릴 혼성 용액을 제조하였다. 그 결과 제조된 혼성 용액의 평균 입도는 아크릴 단량체의 첨가량이 증가함에 따라 증가하였다. 또한 수분산 폴리우레탄-아크릴 혼성 용액으로부터 제조된 코팅 도막의 내마모성과 내화학성은 순수한 PUD 보다 크게 향상되었다.

• 대한전자공학회논문지SD
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• 제43권6호
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• pp.18-22
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• 2006

묽은 n-octadecyltrichlorosilane를 여러 가지 비율로 섞어 만든 유기물에 따라 처리된 $SiO_2$ 절연막의 특성에 대하여 분석하고 펜타센 증착 표면에 생긴 그레인 크기 사이의 상관관계를 조사하였다. 전압-전류 특성 곡선에 의한 누설전류의 증가량이 유기물 처리 농도에 따라 비례적으로 증가하지 않았으며, 0.3 % 처리 농도에서 누설전류가 가장 작게 나타났다. 0.3 % 처리 농도의 $SiO_2$ 절연막은 유무기 복합적인 하이브리드 특성을 나타내고 있으며, 펜타센이 증착된 후 표면 사진에서 그레인 크기가 가장 작게 성장된 것을 확인하였다. 반면에 유기물 특성의 절연막 혹은 무기물 특성의 절연막 위에서 펜타신 물질이 증착후 그레인 크기는 점점 증가하였다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2006년도 춘계학술발표회 초록집
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• pp.137-137
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• 2006

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 추계총회,초청강연,특별강연,연구발표회
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• pp.196.1-196
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• 2000

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2002년도 추계총회 및 연구발표회 초록집
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• pp.180.2-180
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• 2002

• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제33회 하계학술대회 초록집
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• pp.262-262
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• 2007