• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.8
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• pp.1559-1565
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• 2009

Resistivity changes and intermetallic growth after thermal aging of Matter tin-plated copper sheet for current collector in fuel cell were investigated to survey the diffusion of Cu into Sn in interface and surface. The results show that the intermetallic growth and resistivity depended on thermal aging temperature and dwell time. In Sn plate on a Cu substrate, Cu6Sn5(${\mu}$) and Cu3Sn(${\varepsilon}$) intermetallics layer were formed at plate/substrate interface. Cu6Sn5(${\mu}$) intermetallics layer gradually changed Cu3Sn(${\varepsilon}$). Moreover Cu get through Sn layer and it was diffused in the surface at $200^{\circ}C$. On the other hand, only Cu3Sn(${\varepsilon}$) intermetallics layer were formed at plate/substrate interface at $300^{\circ}C$. Consequently, the intermetallics formation, thermal condition and oxidation of surface, causes increase in the resistivity of Tin-plated copper sheet.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.2067_2068
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• 2009

Resistivity changes and intermetallic growth after thermal aging of Matter tin-plated copper sheet for current collector in fuel cell were investigated to survey the diffusion of Cu into Sn in interface and surface. The results show that the intermetallic growth and resistivity depended on thermal aging temperature and dwell time. In Sn plate on a Cu substrate, $Cu_6Sn_5({\mu})$ and $Cu_3Sn({\varepsilon})$ intermetallics layer were formed at plate/substrate interface. $Cu_6Sn_5({\mu})$ intermetallics layer gradually changed $Cu_3Sn({\varepsilon})$. Moreover Cu get through Sn layer and it was diffused in the surface at $200^{\circ}C$. On the other hand, only $Cu_3Sn({\varepsilon})$ intermetallics layer were formed at plate/substrate interface at $300^{\circ}C$. Consequently, the intermetallics formation, thermal condition and oxidation of surface, causes increase in the resistivity of Tin-plated copper sheet.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.3
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• pp.95-100
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• 2016

In this work, tin oxides were obtained by the liquid reduction precipitation method and hydrothermal process using $SnCl_2{\cdot}2H_2O$, $N_2H_4$, and NaOH. Tin oxide crystals having different sizes and morphologies could be achieved. The powders were characterized by X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FE-SEM). Depending on the molar ratio of the raw materials, tin oxide crystalline with the spherical and rectangular plate-like shape could be obtained, the crystal phase was SnO and $Sn_6O_4(OH)_4$. And the obtained SnO crystals by a hydrothermal reaction showed various shapes, such as, spherical, plate-like and flower-like architectures depending on the temperature conditions.

• Journal of Powder Materials
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• v.24 no.5
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• pp.351-356
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• 2017

Tin dioxide nanoparticles are prepared using a newly developed synthesis method of plasma-assisted electrolysis. A high voltage is applied to the tin metal plate to apply a high pressure and temperature to the synthesized oxide layer on the metal surface, producing nanoparticles in a low concentration of sulfuric acid. The particle size, morphology, and size distribution is controlled by the concentration of electrolytes and frequency of the power supply. The as-prepared powder of tin dioxide nanoparticles is used to fabricate a gas sensor to investigate the potential application. The particle-based gas sensor exhibits a short response and recovery time. There is sensitivity to the reduction gas for the gas flowing at rates of 50, 250, and 500 ppm of $H_2S$ gas.

• Journal of Korea Foundry Society
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• v.29 no.1
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• pp.45-51
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• 2009

Conventionally, Al-Sn bearing manufacturing involves casting the Al-Sn alloy and roll-bonding to a steel backing strip. This article will describe the microstructural control of Al-Sn metal bearing alloy following heat treatment. When the pure aluminum rod dipped in the melt of tin maintained below the melting point of aluminum, the melting of aluminum was accelerated with penetration of tin along the grain boundary of aluminum. The length of plate-shaped eutectic tin was decreased with heat treatment time. With even longer heat treatment time over 1 hour the length of eutectic tin didn't decrease any more, while resulting in coarsening of aluminum matrix. Exuded liquid of eutectic tin was formed at the surface of Al-Sn alloy after heat treatment even at below eutectic temperature.

• 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.

• Radiation Oncology Journal
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• v.17 no.3
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• pp.256-260
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• 1999

Purpose : An investigation has been carried out on the factors which affect the response reading of thermoluminescent dosimeters (TLD-100) loaded with thin material in high energy Photon. The aim of the study was to assess the energy response of TLD-100 to the therapeutic ranges of photon beam. Materials and Methods : In this technique, TLD-100 (abbreviated as TLD) chips and three different thin material (Tin, Gold, and Tissue equivalent plastic plate) which mounted on the TLD chip were used in the clinical photon beam. The thickness of each metal plates was 0.1 mm and TE plastic plate was 1 mm thick. These compared with the photon energy dependence of the sensitivities of TLD (normal chip), TLD loaded with Tin or Gold plate, for the photon energy range 6 MV to 15 MV, which was of interest in radiotherapy. Results : The enhancement of surface dose in the TLD with metal plate was clearly detected. The TLD chips with a Gold plate was found to larger response by a factor of 1.83 in 10 MV photon beam with respect to normal chip. The sensitivity of TLD loaded with Tin was less than that for normal TLD and TLD loaded with Gold. The relative sensitivity of TLD loaded with metal has little energy dependence. Conclusion : The good stability and linearity with respect to monitor units of TLD loaded with metal were demonstrated by relative measurements in high energy Photon ($6\~15$ MV) beams. The TLD laminated with metals embedded system in solid water phantom is a suitable detector for relative dose measurements in a small beam size and surface dose.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.131.2-131.2
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• 2007

• Journal of the Korean Ceramic Society
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• v.45 no.3
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• pp.161-166
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• 2008

The multi-films of a metallic film and a transparent conducting oxide (TCO, indium-tin oxide, ITO) film were formed on the stainless steel 316 and 304 plates by a sputtering method and an E-beam method and then the external metallic region of the stainless steel bipolar plates was converted into the metal nitride films through an annealing process. The multi-film formed on the stainless steel bipolar plates showed the XRD patterns of the typical indium-tin oxide, the metallic phase and the metal substrate and the external nitride film. The XRD pattern of the thin film on the bipolar plates modified showed two metal nitride phases of CrN and $Cr_2N$ compound. Surface microstructural morphology of the multi-film deposited bipolar plates was observed by AFM and FE-SEM. The metal nitride film formed on the stainless steel bipolar plates represented a microstructural morphology of fine columnar grains with 10 nm diameter and 60nm length in FE-SEM images. The electrical resistivity of the stainless steel bipolar plates modified was evaluated.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.12
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• pp.1115-1120
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• 2003

In this paper, we investigated the position dependent stress distribution of indium-tin-oxide (ITO) film on Polycarbonate (PC) substrate by external bending force. It was found that there are the maximum crack density at the center position and decreasing crack density as goes to the edge, In accordance with crack distribution, it was observed that the change of electrical resistivity of ITO islands is maximum at the center and decrease as goes to the edge. From the result that crack density is increasing at same island position as face plate distance (L) decreases, it is evident that the more stress is imposed on same island position as L decreases.