Papers by Keyword: Electrical Resistance

Paper TitlePage

Authors: Seong Ho Son, Do Won Chung, Dae Chol Kwon, Hong Kee Lee
Abstract: The thin film resistors such as Ni-Cr alloy could be formed by the electrodeposition method for embedded passive device in printed circuit board. A kinetic study on the electrodeposition of nickel-chromium alloy on copper has been performed using a rotating disk geometry. Activation energies of nickel and chromium in the temperature range between 15°C and 35°C were 8.9kcal/mole and 3.5kcal/mole, respectively. The electrodeposition rate of nickel seems to be controlled partly by electrochemical reaction and partly by mass transport, namely mixed controlled. However, that of chromium seems to be controlled by mass transport. As the amount of chromium in deposit increased, the electric resistance of deposit surface increased. The maximum electric resistance of nickel-chromium alloy deposit was 78.6Ω /□.
Authors: Anežka Lengálová, Petr Slobodian, Robert Olejnik, Pavel Riha
Abstract: A sensing element made of conductive composite created by an entangled network of electrically conductive carbon nanotubes embedded in polyurethane was used for simultaneous measurements of the pressure between the shoe and floor as well as the extension of the leg at the knee joint during marching. The results recorded as sensor resistance change show reasonable reversibility of the basic sensor characteristics, which gives potential for practical applications.
Authors: Enrique Rocha-Rangel, José G. Miranda-Hernández
Abstract: Through an intense mixing process of Al2O3 powder with different copper contents, Al2O3-Cu composites were fabricated by sintered at 1300°C during 1h, where the likely liquid sintering mechanism, lead to obtain composites with relative densities greater than 95%. Scanning electron microscopy was used to observe the resulting microstructures, which indicated that these composites were mostly formed by a fine and homogeneous Al2O3-ceramic matrix with immerse nano-metallic copper particles. The behavior of both fracture toughness and electrical resistance of the composites is directly dependent with the copper content in the matrix. As the copper contents increased, the composites exhibited high values of fracture toughness, whereas, their electrical resistance is reduced considerably.
Authors: Natalija Baribina, Ilze Baltina, Alexander Oks
Abstract: The conductive yarn is an essential component of the smart textile making the product light and comfortable to wear. Nevertheless, one of the most common problems is care that limits the use of the product. Application of additional coating to the yarn renders it water-repellent properties and allows reduction of the negative impact of water on its performance. During the research additional coatings were applied to conductive yarns, with the aim of minimizing electrical resistivity changes caused by washing cycles. Two types of coatings were applied to the yarns, they were washed and tested. The article describes changes in the electrical resistance of different conductors depending on the linear density of the yarn, the type of coating applied and the number of washing cycles. The electrical resistance of electrically conductive yarns increases with washing until they become non-conductive. The electrical resistance of non-textured yarns increases more slowly and the smaller increase is observed in thick yarns. The water-repellent silicone coating applied to yarns reduces the electrical resistance increase rate and the yarns retain their conductivity over more washing cycles.
Authors: Kazuhiro Masuda, Goroh Itoh, Nobuhide Itoh
Abstract: In recent years, reducing carbon dioxide is being demanded in terms of preventing global warming. Lightening autobodies is one of the most practical ways to conduct it, for which converting the body sheets from conventional steel to Al-Mg-Si alloy is effective. Although the Al-Mg-Si alloys have the advantage that they have hardenability during paint baking and do not cause stretcher strain patterns, poor formability is a crucial drawback. Bendability is one of the most important properties related to formability. However, there has been no assessing method having both speediness and quantitative reproducibility. In this study, we have developed a assessing method based on the electric resistance decrease arising from the decrease in conducting section when cracks are formed by bending. Bendability was assessed by electrical resistance change as well as by crack density on the tension surface measured with an SEM. It was found that the new method have far greater speediness with the same quantitative reproducibility than the crack measurement method.
Authors: Pia C. Lansåker, Klas Gunnarsson, Arne Roos, Gunnar A. Niklasson, Claes Goran Granqvist
Abstract: Thin films of Au were made by sputter deposition onto glass substrates with and without transparent and electrically conducting layers of SnO2:In. The Au films were up to ~11 nm in thickness and covered the range for thin film growth from discrete islands, via large scale coalescence and formation of a meandering conducting network, to the formation of a more or less “holey” film. Scanning electron microscopy and atomic force microscopy showed that the SnO2:In films were considerably rougher than the glass itself. This roughness influenced the Au film formation so that large scale coalescence set in at a somewhat larger thickness for films on SnO2:In than on glass. Measurements of spectral optical transmittance and electrical resistance could be reconciled with impeded Au film formation on the SnO2:In layer, leading to pronounced “plateaus” in the near infrared optical properties for Au films on SnO2:In and an accompanying change from such two-layer films having a lower resistance than the single gold film at thicknesses below large scale coalescence to the opposite behavior for larger film thicknesses.
Authors: Gundati Sudheer Kumar, D. Vishnupriya, Ralph Antao, T. Umasankar Patro
Abstract: Acid-functionalized carbon nanotube (fCNT)-poly (vinylidene fluoride) (PVDF) composite films with different CNT contents (0-0.5wt%) were prepared by melt-blending followed by compression molding. The electrical resistance (R) of the composite films under tensile loading was measured by a two-probe method using a custom made equipment connected to digital multimeter. The films (0.35 and 0.5wt% fCNT composites) showed exponential increases in R with displacement after attaining the elastic strain. Further, the change in resistance divided by resistance (ΔR/R) showed a linear increase with strain (ε). The slope of the linear region is found to be higher for 0.35wt% fCNT composite (5.4) as compared to 0.5wt% fCNT composite (3.4), indicating a better sensitivity in the former case. This may be due to less number of electrical conducting paths in case of 0.35fCNT composite. On account of the results obtained, the composites promise as potential candidates for strain sensing in health monitoring.
Authors: Amin Firouzi, Shafreeza Sobri, Faizah Mohd Yasin, Fakhru'l Razi Ahmadun
Abstract: This research was carried out to investigate the effect of gas adsorption towards the electrical resistance of carbon nanotubes (CNTs) thin film. CNTs were synthesized by Floating Catalyst Chemical Vapor Deposition (FC-CVD) method on quartz substrate at 950°C under methane gas flow rate of 150 Standard Cubic Centimeters per Minute (SCCM). Then, the electrical resistance of CNTs was measured by exposing the sensors to CO2 and CH4 gases operating at room temperature. The sensors showed high responses to the gaseous molecules. In the same experimental conditions, the recovery of the sensors was different for CO2 and CH4. It was also observed that the CNTs device behaves as a p-type semiconductor when exposed to gaseous molecules. The fabrication process was relatively simple and did not require special techniques.
Authors: Piotr Wyzga, Lucyna Jaworska, Piotr Putyra, Marcin Podsiadlo, Jolanta Cyboron
Abstract: High hardness, good thermal and electrical conductivity make carbides technologically important materials. The high melting temperature and low coefficients of self-diffusion make it difficult to obtain full dense material. In this paper the results of Spark Plasma Sintering (SPS) of transition metal carbides: NbC, TaC, TiC, ZrC, VC with the addition of graphene 10-20 nm x 14 microns in an amount of 2.5 mass % are presented. Powders were mixed in isopropyl alcohol in a planetary ball mill for 1h. The sintering processes was carried out at 2200°C at two different times: 5 and 30 min. Microstructure of the samples was analyzed using scanning electron microscopy. The measurements of density, Young's modulus hardness and electrical properties were carried out, also. The best properties were obtained for titanium carbide powder, sintered for 30 min. The most significant density increase of the sintered carbide–graphene composite by about 5.3% (depending on increasing sintering duration) was obtained for niobium carbide, while the smallest densities change for zirconium carbide.
Showing 1 to 10 of 72 Paper Titles