• Title/Summary/Keyword: stainless steel coating

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Study on the Tic Coating of Steel by C.V.D. Process (CVD법에 의한 강의 TiC 피복에 관하여)

  • 강국해;최진일;영동영
    • Journal of the Korean institute of surface engineering
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    • v.15 no.4
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    • pp.208-217
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    • 1982
  • To study the effect of TiC coating on weight change, microhardness, wear and heat - resistance of TiC layer, chemical vapour deposition on the various substrates has been carried out with the gaseous mixture of TiCl4, toluene, and H2 in the temperature range of 900 - 1000$^{\circ}C$. The results obtained are as follows ; (1) There is a limited value of carrier and reductant H2 gas flow rate, above which deteriorate effect on the TiC depoition arises (2) Increased thickness of TiC layer was resulted with increasing temperature and time. Better deposition was obtained with stainless steels and the best results were introduced by cobalt coating of substrates. (3) Wear resistance of the TiC coated specimen improved markedly. Heat resistivity of the coated steel showed excellent result, whereas the coated stainless Steels were infer-ior to the substrate.

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Morphologies of Brazed NiO-YSZ/316 Stainless Steel Using B-Ni2 Brazing Filler Alloy in a Solid Oxide Fuel Cell System

  • Lee, Sung-Kyu;Kang, Kyoung-Hoon;Hong, Hyun-Seon;Woo, Sang-Kook
    • Journal of Powder Materials
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    • v.18 no.5
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    • pp.430-436
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    • 2011
  • Joining of NiO-YSZ to 316 stainless steel was carried out with B-Ni2 brazing alloy (3 wt% Fe, 4.5 wt% Si, 3.2 wt% B, 7 wt% Cr, Ni-balance, m.p. 971-$999^{\circ}C$) to seal the NiO-YSZ anode/316 stainless steel interconnect structure in a SOFC. In the present research, interfacial (chemical) reactions during brazing at the NiO-YSZ/316 stainless steel interconnect were enhanced by the two processing methods, a) addition of an electroless nickel plate to NiO-YSZ as a coating or b) deposition of titanium layer onto NiO-YSZ by magnetron plasma sputtering method, with process variables and procedures optimized during the pre-processing. Brazing was performed in a cold-wall vacuum furnace at $1080^{\circ}C$. Post-brazing interfacial morphologies between NiO-YSZ and 316 stainless steel were examined by SEM and EDS methods. The results indicate that B-Ni2 brazing filler alloy was fused fully during brazing and continuous interfacial layer formation depended on the method of pre-coating NiO-YSZ. The inter-diffusion of elements was promoted by titanium-deposition: the diffusion reaction thickness of the interfacial area was reduced to less than 5 ${\mu}m$ compared to 100 ${\mu}m$ for electroless nickel-deposited NiO-YSZ cermet.

Characteristics of Fluorine-Doped Tin Oxide Film Coated on SUS 316 Bipolar Plates for PEMFCs (ECR-MOCVD를 이용하여 연료 전지 분리판에 코팅된 FTO막의 특성 연구)

  • Park, Ji-Hun;Hudaya, C.;Jeon, Bup-Ju;Byun, Dong-Jin;Lee, Joong-Kee
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.3
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    • pp.283-291
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    • 2011
  • Polymer electrolyte membrane fuel cells (PEMFCs) use the bipolar plate of various materials between electrolyte and contact electrode for the stable hydrogen ion exchange activation. The bipolar plate of various materials has representatively graphite and stainless steel. Specially, stainless steels have advantage for low cost and high product rate. In this study, SUS 316 was effectively coated with 600 nm thick F-doped tin oxide (SnOx:F) by electron cyclotron resonance-metal organic chemical vapor deposition and investigated in simulated fuel cell bipolar plates. The results showed that an F-doped tin oxide (SnOx:F) coating enhanced the corrosion resistance of the alloys in fuel cell bipolar plates, though the substrate steel has a significant influence on the behavior of the coating. Coating SUS 316 for fuel cell bipolar plates steel further improved the already excellent corrosion resistance of this material. After coating, the increased ICR values of the coated steels compared to those of the fresh steels. The SnOx:F coating seems to add an additional resistance to the native air-formed film on these stainless steels.

Effectiveness of medical coating materials in decreasing friction between orthodontic brackets and archwires

  • Arici, Nursel;Akdeniz, Berat S.;Oz, Abdullah A.;Gencer, Yucel;Tarakci, Mehmet;Arici, Selim
    • The korean journal of orthodontics
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    • v.51 no.4
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    • pp.270-281
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    • 2021
  • Objective: The aim of this in vitro study was to evaluate the changes in friction between orthodontic brackets and archwires coated with aluminum oxide (Al2O3), titanium nitride (TiN), or chromium nitride (CrN). In addition, the resistance of the coatings to intraoral conditions was evaluated. Methods: Stainless steel canine brackets, 0.016-inch round nickel-titanium archwires, and 0.019 × 0.025-inch stainless steel archwires were coated with Al2O3, TiN, and CrN using radio frequency magnetron sputtering. The coated materials were examined using scanning electron microscopy, an X-ray diffractometer, atomic force microscopy, and surface profilometry. In addition, the samples were subjected to thermal cycling and in vitro brushing tests, and the effects of the simulated intraoral conditions on the coating structure were evaluated. Results: Coating of the metal bracket as well as nickel-titanium archwire with Al2O3 reduced the coefficients of friction (CoFs) for the bracket-archwire combination (p < 0.01). When the bracket and stainless steel archwire were coated with Al2O3 and TiN, the CoFs were significantly lower (0.207 and 0.372, respectively) than that recorded when this bracket-archwire combination was left uncoated (0.552; p < 0.01). The friction, thermal, and brushing tests did not deteriorate the overall quality of the Al2O3 coatings; however, some small areas of peeling were evident for the TiN coatings, whereas comparatively larger areas of peeling were observed for the CrN coatings. Conclusions: Our findings suggest that the CoFs for metal bracket-archwire combinations used in orthodontic treatment can be decreased by coating with Al2O3 and TiN thin films.

A Study on Plasma Sprayed Porous Super Austenitic Stainless Steel Coating for Improvement of Bone Ingrowth (Bone ingrowth 향상을 위해 플라즈마 용사된 초내식성 오스테나이트 스테인리스강의 다공성 코팅층에 대한 연구)

  • 오근택;박용수
    • Journal of the Korean institute of surface engineering
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    • v.29 no.2
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    • pp.81-92
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    • 1996
  • The cementless fixation of bone ingrowth by porous coatings on artificial hip joint prostheses are replacing polymethylmethacrylate(PMMA) bone cement fixations. However, the major interests in the field of porous metal coating are environmental corrosivity accelerated by metal ion release, deterioration in the mechanical property of the coating, and the mechanical failure of the coatings as well as the substrate. Therefore, the selection of right materials for coatings and the development of porous coating techniques must be accomplished. Because of the existing problems in Ti and Ti alloys which are used extensively, this study is focused on the plasma spraying technique for coating on super stainless steel substrate. In order to determine the optimum conditions which satisfy the requirement for the porous coatings, under the plasma spraying, we selected the experimental parameters which extensively influenced on the characteristics of the coating through the pre-examination. Spray distance has been selected among 120, 160, and 200mm and primary gas flow rate among 70, 100, and 130 SCFH. Current and secondary gas($H_2$) flow rate was fixed at 400A, and 15 SCFH respectively. To understand the characteristics of the coatings, surface morphology, cross-sectional micro-structure, surface roughness, residual stress, and corrosion resistance were elucidated and the best conditions for the bone ingrowth improvement on artificial hip joint prostheses were found.

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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
    • Transactions of the Korean hydrogen and new energy society
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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.

A Study on the Ceramic Coating of Biopsy Needle (조직생검용 Needle의 세라믹 코팅에 관한 연구)

  • Cho, Sung-Man;Chung, Hyup-Jae;Kim, Man-Tae;Rhee, Kyong-Yop
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.9
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    • pp.121-126
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    • 2009
  • Stainless steel 316L (STS 316L) is widely used as a material of biopsy needle. However it has a side effect that tissue can be damaged by electrochemical operation between tissue and STS 316L. Many studies have been made on the ceramic coating of biopsy needle to reduce the side effect. In this study, STS 316L was coated with three bioceramics, $Al_2O_3$, $SiO_2$ and $ZrO_2$ using a RF magnetron sputtering method. The effects of ceramic coating on the electrical conductivity and coating strength of ceramic-coated STS 316L were investigated. The results showed that the electrical conductivity of ceramic-coated STS 316L was much lower than that of uncoated STS 316L. The coating strength of $ZrO_2$-coated STS 316L was 30% and 70% higher, respectively than those of $Al_2O_3$-coated STS 316L and $SiO_2_3$-coated STS 316L.

Electrodeposition of Zr on AISI 304 Stainless Steel in Molten Chlorides. (염화물계 혼합염욕중에서 AISI 304 Srainless Steel의 Zr 전해피복에 관한연구)

  • 반장호;백영현
    • Journal of the Korean institute of surface engineering
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    • v.30 no.3
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    • pp.159-166
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    • 1997
  • The metalliding technique was adopted to obtain the diffusion coating of zirconium on AISI 304 Stainless Steel in molten mixed chlorides (32.9wt.%LICl-34.8wt.%NaCl-32.3wt.%). Experiments were carried out in argon gas atmosphere. The electrolytic cell was consisted of a AISI 304 Stainless steel cathode and a consumable zirconium anode. The quality of deposit was analysed by SEM, Optical Microscope, EDS, and also examined by the Micro-Vickers hardness and corrosion tests. Interface of deposit layer was identified as zirconium-iron alloy layer caused by diffusion process at elevated temperatures. The optimum condition for the metalliding was found to be the bath temperature of $550^{\circ}C$, the concentration of $K_2ZrF_6$ ,5wt.%, cathodic current derrent density of 7.0 to 10.0mA/$\textrm{cm}^2$ , and anodic current density of 2.0mA/$\textrm{cm}^2$.

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Multi-layered Coating Deposited on PEMFC (Proton Exchange Membrane Fuel Cell) Bipolar Plates (고분자전해질 연료전지용 바이폴라 플레이트의 다층 코팅의 증착)

  • Yun, Young-Hoon;Chung, Hoon-Taek;Cha, In-Su;Choi, Jeong-Sik;Kim, Dong-Mook;Jung, Jin-Ho
    • Journal of the Korean Ceramic Society
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    • v.45 no.8
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    • pp.472-476
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    • 2008
  • The surface region of commercial stainless steel 304 and 316 plates has been modified through deposition of the multi-layered coatings composed of titanium film ($0.1{\mu}m$) and gold film ($1-2{\mu}m$) by an electron beam evaporation method. XRD patterns of the stainless steel plates deposited with conductive metal films showed the peaks of the external gold film and the stainless steel substrate. Surface microstructural morphologies of the stainless steel bipolar plates modified with multi-layered coatings were observed by AFM and FE-SEM images. The stainless steel plates modified with $0.1{\mu}m$ titanium film and $1{\mu}m$ gold film showed microstructure of grains of under 100 nm diameter. The external surface of the stainless steel plates deposited with $0.1{\mu}m$ titanium film and $2{\mu}m$ gold film represented somewhat grain growth of Au grains in FE-SEM image. The electrical resistance and water contact angle of the stainless steel bipolar plates modified with multi-layered coatings were examined with the thickness of the gold film.