• Title/Summary/Keyword: coated rate

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The Tin coating for life-eztension on the cutting bites. (절삭가공용 바이트 수명연장을 위한 TiN 코팅에 관한 연구)

  • 백영남;유송민;오환섭;전인철;김강법
    • Journal of the Korean institute of surface engineering
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    • v.31 no.6
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    • pp.400-406
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    • 1998
  • Tool life characteristics were investigated for the TiN coated (PVD) tungsten carbide cutting tools to improve the tool life Experimental variables for Tin coating were coating time and cathode bias voltage and cuting variables were cutting speed and feel rate. As a experiment result, TiN coated tool was extended about from 2.14 to 2.7 times than that of not coated tungsten carbide tools. Also, coating thinkness is much affected to tool life.

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A study of transmittance and color change of various photochromic lenses by an UVA lamp (UVA광원에 의한 Photochromic lens의 색비율 제어에 관한 연구)

  • Lim, Yong-Moo;Jung, Ju Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.8 no.2
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    • pp.185-191
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    • 2003
  • In this study, We measured transmittance and color change of various photochromic lens as a function of temperature(6, 12, $28^{\circ}C$), irradiation time of UVA lamp and the types of materials(plastic and glass) and distribution of photochromic ingredients(coated and bulk type). The coated-type photochromic lens showed higher saturated value than bulk-type lens without regard to temperature. And darkening rate of smoke color lenses were higher compare to brown lens in case of glass photochromic lens. All of photochromic lens passed ANSI Z80.3 regulation in transmittance and color independent of temperature. The saturated values of plastic photochromic lens excluded coated-type and glass photochromic lens were ranked as cosmetic use. The saturated value of coated-type. Tbr and TMs were general applications in $6^{\circ}C$ and $12^{\circ}C$, but cosmetic purpose in $28^{\circ}C$. The darkening rate was increased with decreasing temperature, whereas the fading rate became higher with increasing temperature.

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Corrosion Resistance of Zn and Cu Coated Steel Pipes as a Substitute for Cu Pipe in an Air Conditioner System

  • Shin, Jae-Gyeong;Park, Chan-Jin;Hong, Sung-Kil
    • Corrosion Science and Technology
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    • v.8 no.1
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    • pp.40-43
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    • 2009
  • We investigated the corrosion resistance of Zn and Cu coated steel pipes as a substitute for Cu pipe in an air-conditioner system. In addition, the galvanic corrosion tendency between two dissimilar metal parts was studied. The corrosion resistance of the Cu electroplated steel was similar to that of Cu, while the corrosion rate of the Zn electro- galvanized and the galvalume (Zn-55 % Al) coated steels was much higher and not suitable for Cu substitute in artificial sea water and acidic rain environments. Furthermore, the galvanic difference between Cu electroplated steel and Cu was so small that the Cu coated steel pipe can be used as a substitute for Cu pipe in an air-conditioner system.

Nanofiller as Crosslinker for Halogen-Containing Elastomers

  • Sahoo, N.G.;Kumar, E.Shiva;Das, C.K.;Panda, A.B.;Pramanik, P.
    • Macromolecular Research
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    • v.11 no.6
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    • pp.506-510
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    • 2003
  • A Zn ion-coated nanosilica filler has been developed and tested, in chlorosulfonated polyethylene (CSPE) and polychloroprene (CR), as a vulcanizing activator, cum was reinforcing filler. In this study, ZnO was replaced by the Zn ion-coated nanosilica filler with an aim of studying the dual role of this nanofiller in CSPE and CR. In the case of CSPE vulcanizates, the presence of MgO deteriorated the state and rate of cure when the Zn ion-coated nanosilica filler was used, but in the case of CR it improved the state of cure and enhanced the modulus and tensile strength. The Zn ion-coated filler proved to be a better reinforcing-cum-curing agent than was externally added ZnO and NA-22 also proved to be a better curative in the presence of the Zn ion-coated nanosilica filler for both CSPE and CR.

The Effect on the Dissolution Rate of Sulfanilamide Granules Coated with a Polyelectrolyte Complex of Sodium Tripolyphosphate-Chitosan (Sodium Tripolyphosphate-Chitosan의 Polyelectrolyte Complex Coating이 Sulfanilamide 과립의 용출에 미치는 영향)

  • Ku, Young-Soon;Kim, Ja-Young;Kim, Kil-Soo
    • YAKHAK HOEJI
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    • v.33 no.6
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    • pp.324-332
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    • 1989
  • Drug release from sulfanilamide granules coated with a polyelectrlyte complex of sodium tripolyphosphate and chitosan was studied. The coating film thickness increased with increasing concentration of chitosan in the coating solution and the drug release rates of the coated granules were significantly reduced comparing with those of the uncoated granules. $T_{50%}$ of the uncoated granules was 6 minutes, but those of the granules coated with chitosan-sodium tripolyphosphate from 0.5, 0.7, and 0.9% (w/v) chitosan-HCl solution were 27, 135, and 180 minutes, respectively in distilled water. In dissolution medium at pH 6.8, $T_{50%}$ of the uncoated granules was 4 minutes, but those of the granules coated with chitosan-sodium tripolyphosphate from 0.5, 0.7, and 0.9(w/v)% chitosan-HCl solution, were 32, 135, and 160 minutes, respectively.

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A Study on the Performance of PEMFC Using the TiN-Coated 316 Stainless Steel Bipolar Plates (TiN이 코팅된 316 스테인리스강 분리판을 이용한 고분자전해질 연료전지의 성능에 관한 연구)

  • Cho, Eun-Ae
    • Journal of Hydrogen and New Energy
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    • v.14 no.4
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    • pp.291-297
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    • 2003
  • As an alternative bipolar plate material for polymer electrolyte membrane fuel cell (PEMFC), TiN-coated 316 stainless was evaluated in terms of electrical contact resistance and water contact angle. Performance and lifetime of the TiN-coated 316 bipolar plates were measured in comparison with those of graphite and bare 316 bipolar plates. At a cell voltage of 0.6 V, current density of the single cells using graphite, AISI 316, and TiN/316 bipolar plates was 996, 796, and $896mA/cm^2$, respectively. By coating 316 stainless steel with TiN layer, performance degradation rate determined to be the voltage degradation rate at a cell voltage of 0.6 V was reduced from 2.3 to 0.43 mV/h.

The Shielding Effectiveness of Zn-Al Arc Thermal Metal Film Coated Cement-Mortar Using Copper Powder (Zn-Al 아크 금속용사 피막을 적용한 구리분말 혼입 시멘트 모르타르의 전자파 차폐 성능 평가)

  • Choi, Hyun-Jun;Choi, Hyun-Kuk;Kim, Hyeong-Cheol;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.05a
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    • pp.124-125
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    • 2017
  • In this study, the shielding effectiveness of the Zn-Al arc thermal metal film coated cement-mortar mixed with copper powder by reflection, absorption, multi-reflection loss in 2.25~2.65 GHz was reviewed. By enhancing the mixing ratio of copper powder, the shielding effectiveness by absorption and multi-reflection loss was increased, but shielding rate(%) based on 80 dB showed below 20%. The Zn-Al arc thermal metal film coated on specimen, the shielding rate increased 3.5 times by reflection loss.

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Fabrication of NiO buffer film on textured Ni substrate for YBCO coated conductor (Textured Ni 기판 위에 YBCO coated conductor 모재용 NiO 완충층 제조)

  • Sun, Jong-Won;Kim, Hyoung-Seop;Jung, Choon-Ghwan;Lee, Hee-Gyoun
    • Progress in Superconductivity
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    • v.3 no.1
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    • pp.125-129
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    • 2001
  • NiO buffer layers were deposited on texture Ni tapes fur YBCO coated conductors by MOCVD(metal organic chemical vapor deposition) method, using a single solution source. Variables were deposition temperature and flow rate of $0_2$carrier gas. At higher temperatures, The NiO(111) texture was well developed, but the NiO(200) texture was developed at low temperatures. The best result was obtained at the deposition temperature of$ 470^{\circ}C$ and the gas flow rate of 200 sccm. FWHM value of $\omega$-scan fur NiO(200) of the film and $\Phi$-scan for NiO(111) of the film was $4.2^{\circ}$ and $7^{\circ}$, respectively.

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A Study on Surface Roughness in Circular Pocket Machining of SCM415 Steel (SCM415강의 원형포켓 가공시 표면 거칠기에 관한 연구)

  • Choi, Chul-Woong
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.7
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    • pp.77-82
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    • 2019
  • In this study, we study the change of surface roughness during cutting machining by changing the cutting conditions such as feed rate and spindle velocity with chromium molybdenum steel (SCM415) material and TiCN and TiAlN coated end mill tools. The surface roughness value of the test specimen for SCM415, was found to be 3,000 rpm in TiCN coated end mill and $0.634{\mu}m$ in surface roughness at a feed rate of 100 mm/min. In the TiAlN coated end mill, 300 mm/min, the surface roughness was the best at $0.699{\mu}m$. The overall average surface roughness of each coating tool was better than that of TiAlN.

Separator Properties of Silk-Woven Fabrics Coated with PVdF-HFP and Silica and the Charge-Discharge Characteristics of Lithium-ion Batteries Adopting Them (PVdF-HFP와 실리카가 코팅된 실크 견직물의 분리막 특성과 이를 채용한 리튬이온전지의 충방전 특성)

  • Oh, Seem Geon;Lee, Young-Gi;Kim, Kwang Man;Lee, Yong Min;Kim, Sang Hern;Kim, Yong Joo;Ko, Jang Myoun
    • Korean Chemical Engineering Research
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    • v.51 no.3
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    • pp.330-334
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    • 2013
  • Mixtures of poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) and silica nanoparticles are coated on the surface of a silk fabrics separator. The coated separators are finally prepared by injecting an electrolyte solution and then characterized for use of lithium-ion battery separator/electrolyte. In the preparation, various contents of dibutylphthalate (DBP) as a plasticizer are used to enhance the formation of micropores within the coated membrane. The coated silk fabrics separators are characterized in terms of ionic conductivity, drenching rate, and electrochemical stability, and the charge-discharge profiles of lithium-ion batteries adopting the coated separators are also examined. As a result, the coated silk fabrics separator prepared using DBP 40~50 wt% and silica shows the superior separator properties and high-rate capability. This is due to (i) high sustainability of silk fabrics, (ii) the formation of micropores with the coated layer membrane by DBP, (iii) increase in drenching rate by silica nanoparticles to involve great enhancements in specific surface area and ionic conductivity.