• Title/Summary/Keyword: Nickel coating

Search Result 19, Processing Time 0.227 seconds

Corrosion Behavior of Anode Current Collectors in Molten Carbonate Fuel Cells (용융탄산염 연료전지 Anode부 집전판의 부식특성)

  • Han, Won-Kyu;Ju, Jeong-Woon;Shin, Jung-Cheol;Kang, Sung-Goon;Jun, Joong-Hwan;Lim, Hee-Chun
    • Korean Journal of Materials Research
    • /
    • v.18 no.5
    • /
    • pp.259-265
    • /
    • 2008
  • The corrosion and degradation factors of a current collector in a molten carbonate fuel cell (MCFC) were investigated to determine the optimized coating thickness of nickel on STS316L. The results show that the surface morphology and electrical properties depended on the nickel coating thickness. The surface morphology gradually changed from a flat to a porous structure along as the nickel coating thickness decreased, and the electrical resistance of the nickel-coated STS316L increased as the nickel coating thickness decreased. This can be attributed to the diffusion of elements of Fe and Cr from the substrate through the nickel grain boundaries. Additionally, carburization in the metal grains or grain boundaries in an anodic environment was found to influence the electrical properties due to matrix distortion. The resistance of Cr-oxide layers formed in an anodic environment causes a drop in the potential, resulting in a decrease in the system efficiency.

Thermal Analysis Comparison of Continuous Casting Mold (연속주조 몰드의 열해석 비교)

  • 원종진;이종선;윤희중;이현곤
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • /
    • pp.200-205
    • /
    • 2000
  • This study is object to thermal analysis comparison of continuous casting mold. A two-dimensional transient finite element model was developed to compute the temperature distribution for continuous casting mold. For thermal analysis using analysis result from ANSYS. In other to thermal analysis of continuous casting mold, many variables such as casting speed, cooling condition, film coefficient, convection and load condition are considered.

  • PDF

Structural Analysis Comparison of Continuous Casting Mold (연속주조 몰드의 구조해석 비교)

  • 원종진;이종선;홍석주;이현곤
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • /
    • pp.181-187
    • /
    • 2000
  • This study is object to structural analysis comparison of continuous casting mold. A two-dimensional finite element model was developed to compute the temperature distribution, thermal stress and thermal strain behavior for continuous casting mold. For structural analysis using thermal analysis result from ANSYS. In other to structural analysis of continuous casting mold, many variables such as casting speed, cooling condition, film coefficient, convection and load condition are considered.

  • PDF

Fabrication and Thermophysical Properties of Nickel-coated Aluminum Powder by Electroless Plating (비전해 방법을 이용한 니켈 코팅 알루미늄 분말 제조 및 열물성 평가)

  • Lee, Sanghyup;Lim, Jihwan;Noh, Kwanyoung;Yoon, Woongsup
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.18 no.4
    • /
    • pp.9-17
    • /
    • 2014
  • In this study, in order to improve the ignitability of high energy aluminum powder, natural oxide films (alumina) were chemically removed, and instead nickel coat was applied. We used an electroless plating for nickel coating and confirmed quantitatively and qualitatively a time-dependent degree of nickel coating through analysis of surface by SEM/EDS. We also conducted element analysis by XRD and thermal properties by TGA/DSC in air oxidizer environment. There results explained the ignition enhancement mechanism of the nickel-coated aluminum powder in air. The difference between coated and un-coated aluminum powder, the effectiveness of coated powder has better ignitability.

Mechanical and Tribological Properties of Pulse and Direct Current Electrodeposited Ni-TiO2 Nano Composite Coatings

  • Gyawali, Gobinda;Woo, Dong-Jin;Lee, Soo-Wohn
    • Journal of the Korean institute of surface engineering
    • /
    • v.43 no.6
    • /
    • pp.283-288
    • /
    • 2010
  • Ni-$TiO_2$ nano composite coatings were fabricated using pulse current electrodeposition technique at 100 Hz pulse frequency with a constant 50% pulse duty cycles and reference was taken with respect to the direct current (dc) electrodeposition. The properties of the composite coatings were investigated by using SEM, XRD, Wear test and Vicker's microhardness test. Pulse electrodeposited composite has exhibited enhancement of (111), (220), and (311) diffraction lines with an attenuation of (200) line. The results demonstrated that the microhardness of composite coatings under pulse condition was significantly improved than that of pure nickel coating as well as dc electrodeposited Ni-$TiO_2$ composite coatings. Wear tracks have shown the less plastic deformation in pulse plated composite. Coefficient of friction was also found to be lower in pulse plated composite coatings as compared to dc plated composite coatings.

Characterization of Nickel-coated Silver Nanowire Flexible Transparent Electrodes with a Random-mesh Structure Formed by Bubble Control (거품 제어에 의해 형성된 무정형 그물망 구조의 니켈이 코팅된 은나노와이어 유연 투명전극의 특성 분석)

  • Park, Jong Seol;Park, Tae Gon;Park, Jin Seok
    • Journal of the Semiconductor & Display Technology
    • /
    • v.19 no.3
    • /
    • pp.36-42
    • /
    • 2020
  • Silver nanowire (AgNW) random-meshes with high transmittance, low sheet resistance, and high oxidation stability and flexibility were fabricated using solution-based processes. The random-mesh structure was obtained by forming bubbles whose sizes and densities were controlled using a corona treatment of polyethylene terephthalate (PET) substrates. To reduce the sheet resistance of the fabricated AgNW electrode, a washing process using ethanol solution was performed. In addition, nickel (Ni) was coated on AgNW to improve resistance to oxidation. The effects of corona treatment and Ni-coating on the transmittance, sheet resistance, oxidation stability, and flexibility of the AgNW electrodes were investigated.

  • PDF

Preparation and Characterization of Highly Conductive Nickel-coated Glass Fibers

  • Kim, Byung-Joo;Choi, Woong-Ki;Song, Heung-Sub;Park, Jong-Kyoo;Lee, Jae-Yeol;Park, Soo-Jin
    • Carbon letters
    • /
    • v.9 no.2
    • /
    • pp.105-107
    • /
    • 2008
  • In this work, we employed an electroless nickel plating on glass fibers in order to enhance the electric conductivity of fibers. And the effects of metal content and plating time on the conductivity of fibers were investigated. From the results, island-like metal clusters were found on the fiber surfaces in initial plating state, and perfect metallic layers were observed after 10 min of plating time. The thickness of metallic layers on fiber surfaces was proportion to plating time, and the electric conductivity showed similar trends. The nickel cluster sizes on fibers decreased with increasing plating time, indicating that surface energetics of the fibers could become more homogeneous and make well-packed metallic layers, resulting in the high conductivity of Ni/glass fibers.

Specimen Tests for a Process Development of the Electro-Nickel/Chrome Coating for a Thrust Chamber (연소기 적용 전해니켈/크롬도금 공정개발을 위한 시편시험)

  • Lim, Byoung-Jik;Ryu, Chul-Sung;Choi, Hwan-Seok
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • /
    • pp.113-116
    • /
    • 2011
  • A total of 9 coating specimens were fabricated through 3 different processes to evaluate the availability and performance of a nickel/chrome coating for the protection of the inner wall of a thrust chamber operating on a condition of high temperature and pressure. Thickness and thermal conductivity of the specimens were measured and thermal shock test was conducted.

  • PDF