Nickel Tapes Research Articles

Induction heating for desorption of surface contamination for high-repetition laser-driven carbon-ion acceleration

This study reports the first experimental demonstration of surface contamination cleaning from a high-repetition supply of thin-tape targets for laser-driven carbon-ion acceleration. The adsorption of contaminants containing protons, mainly water vapor and hydrocarbons, on the surface of materials exposed to low vacuum (>10−3 Pa) suppresses carbon-ion acceleration. The newly developed contamination cleaner heats a 5-μm-thick nickel tape to over 400 °C in 100 ms by induction heating. In the future, this heating method could be scaled to laser-driven carbon-ion acceleration at rates beyond 10 Hz. The contaminant hydrogen is eliminated from the heated nickel surface, and a carbon source layer—derived from the contaminant carbon—is spontaneously formed by the catalytic effect of nickel. The species of ions accelerated from the nickel film heated to various temperatures have been observed experimentally. When the nickel film is heated beyond ∼150 °C, the proton signal considerably decreases, with a remarkable increase in the number and energy of carbon ions. The Langmuir adsorption model adequately explains the temperature dependence of desorption and re-adsorption of the adsorbed molecules on a heated target surface, and the temperature required for proton-free carbon-ion acceleration can be estimated.

Conductive materials for connecting tires of multi-element accumulator traction batteries

The article deals with the choice of materials for connecting tires of traction batteries (TB). The optimal parameters of their spot welding with batteries are experimentally established (the first pulse with a current of 7 kA duration of 1 ms, the break between the pulses of 1 ms, the second pulse with a current of 7 kA duration of 2 ms). When operating the traction battery on electric vehicles, the resistance of the connecting tires should not lead to heating of the batteries in order to avoid overheating above 60 °C. In most modern TB, consisting of Li-ion elements, a nickel tape is used for the connection. To ensure the weldability of materials (copper–nickel or nickel–nickel), it is important that the operating temperature is reached at a short-term current pulse in the welding zone. One of the solutions to this problem is the application of a metal coating. Experiments were conducted on the weldability of various materials, including those with applied coatings. The best results in weldability were shown by tires made of tinned copper, which was welded to nickel plates (emitting the battery body). Tear tests of the welded samples were carried out. The tensile strength of the original copper tires was 340–450 MPa. When welding copper–nickel and copper(tinned) – nickel plates, the strength limit values reach 70 % of the strength of the original copper plate. On the basis of the obtained experimental data, a pilot batch of battery TB was manufactured, which successfully passed tests for compliance with the technical requirements for the strength and the value of the transition resistances of the welded joints of connecting buses with batteries.

Pomiar temperatury za pomocą termopary naturalnej podczas szlifowania ściernicą jednowarstwową

Presented is an example of temperature measurement during grinding of high-alloy steels with electroplated cBN grinding wheel. The grinding material and the nickel tape formed a natural thermocouple used for the measurements. A method for gaining the thermal characteristic of natural thermocouple was proposed.

Vibrating sample magnetometer 2D and 3D magnetization effects associated with different initial magnetization states

Differences in VSM magnetization vector rotation associated with various initial magnetization states were demonstrated. Procedures and criteria were developed to select sample orientation and initial magnetization states to allow for the combination of two different 2D measurements runs (with the same field profiles) to generate a dataset that can be representative of actual 3D magnetization rotation. Nickel, cast iron, and low moment magnetic tape media were used to demonstrate these effects using hysteresis and remanent magnetization test sequences. These results can be used to generate 2D and 3D magnetic properties to better characterize magnetic phenomena which are inherently three dimensional. Example applications are magnetic tape-head orientation sensitivity, reinterpretation of 3D coercivity and other standard magnetic properties, and multi-dimensional shielding effectiveness.

SmBa2Cu3O7−δ superconducting layer prepared on NiO buffer layer through fluorine-free chemical method

With energy shortage becoming increasingly severe, the application of high-temperature superconducting material is a considerable prospects, where economic, efficient and energy-saving preparation technology becoming the key factors for the large-scale applications of [Formula: see text] (REBCO) superconducting coated conductors. Currently, non-vacuum chemical solution deposition technique is an important way to reduce the cost of preparation of coated conductors. However, a randomly oriented NiO growth is an important problem for the non-vacuum chemical preparation of superconducting coated conductor. A simple and valid method is to prepare textured NiO film on the bare nickel (Ni) tape. In this paper, NiO films with [Formula: see text]-axis texture were prepared in air and in argon respectively by the surface oxidation epitaxial method. We obtained the smooth and densification NiO films. The layer of [Formula: see text] was fabricated on the NiO film via a fluorine-free chemistry method. The purpose of this paper is to provide a potential value of non-vacuum chemical solution deposition technique for preparation of REBCO superconducting coated conductors.

Development of Textured Coated Superconductor Substrate Tapes by Severe Plastic Deformation Processing

An attempt has been made to fabricate highly cube textured ({001}<100>) polycrystalline nickel substrate tapes for coated superconductor applications using severe plastic deformation route. For this purpose high purity Ni (~99.97%) plates with widely different average grain size (28 µm or fine grained starting material and 650 µm or coarse grained starting material, respectively) are severely deformed by Accumulative Roll Bonding (ARB) up to an equivalent strain level of (εeq = 6.4) and annealed at various temperatures between 300° to 800°C for one hour. Upon annealing at different temperatures, the fine grained starting material developed a much stronger cube texture than the coarse grained starting material. By suitable annealing treatment near 100% cube textured tape could be obtained in the SPD processed fine grained nickel tapes having a predominantly low angle boundary network. The observed difference in the strength of cube texture in the two materials could be explained based on the oriented nucleation mechanism of formation of cube texture. The present results indicate that SPD processing route such as ARB is very effective in fabricating high purity Ni or Ni alloys intended for coated superconductor substrate applications.

The use of pulsed laser deposition to produce low-temperature barium titanate films on nickel tape and carbon fiber fabric

In order to explore the functionalization of wearable fabrics for power generation, barium titanate (BTO) was deposited on nickel tape and on carbon fiber fabric employing pulsed laser deposition (PLD) methods under conditions normally not considered ideal to produce optimum ferroelectric properties, namely, at temperatures as low as 100°C and under various oxygen partial pressures. The remnant charge polarization and film resistance properties were evaluated to determine the effect of the aforementioned deposition conditions. The P–V characterization indicates that the BTO films still retained ferroelectric properties down to 200°C, below which, the behavior was only paraelectric. Piezoelectric measurements were made with a resulting potential of 4 kV/m.

Preparation of NiO Buffer Layer by Direct Oxygenation of Ni Tape

Recently, Nickel-based alloys are widely used for textured substrates tapes. However, the deposition of oxide buffer layers on nickel tapes is required to stop the diffusion of nickel from the tape to superconducting layer and to improve the mismatch between the substrate and superconducting film. Biaxially textured NiO buffer layer is easily formed on cubic textured nickel tape by the technique called surface oxidation epitaxy. In this work, we developed a direct oxygenating method to make the NiO buffer layer on nickel tape. The nickel tape was directly oxygenated in different atmospheres. It is found that in inert atmosphere, a high quality NiO layer can be formed on the surface of the tape. The oxygenating conditions, including atmospheres and temperatures, and their influence on the structure of the NiO buffer layer, were studied in detail and discussed.

Thermal grain-boundary grooving in bicrystal thin solid films having strong anisotropic surface Gibbs free energy represented by the modified cycloid-curtate function

The variational non-equilibrium thermodynamic method is further extended to give full coverage for the tilted grain-boundary (GB) configuration with respect to the sidewalls of a bicrystal thin solid film having strong anisotropic specific surface Gibbs free energy associated with the singular directions (faceting, vicinal planes). A set of critical computer simulation experiments supported by the generalized longitudinal force diagrams is performed on the asymmetrically disposed (inclination) bicrystal thin metallic films having four- and six-fold anisotropic specific surface Gibbs free energy to demonstrate the various GB-groove root topologies caused by the grain-boundary grooving under the surface drift-diffusion driven by the capillarity forces (thermal grooving). In the computer simulations, the strongly anisotropic surface-specific Gibbs free energy associated with the cusp regions is represented by the modified cycloid-curtate function (MCCF) as a basis (generator) for the Dirac delta distribution function on the Wulff construction, which involves not only the Wulff surface roughness (WSR) parameter (anisotropy constant) but also the Wulff surface topography (WST) index (shape parameter) that may be used as a metric for the temperature roughening phenomenon. A special computer run is also designed using the realistic structural and physicochemical properties in order to simulate the thermal groove profiles of cube-textured pure nickel tape {Ni—99.99 wt%} annealed four hours in vacuum at 800 °C, and observed by the atomic force microcopy (AFM). The experimental line width fitting procedure applied to the simulation profile subjected to the self-similarity transformation, which resulted in almost perfect replication of the experimental digitized AFM photography, has yielded a mean surface (mass) diffusivity of nickel about 5.7×10 −13 m 2/s (800 °C), which is in excellent quantitative agreement with the diffusivity relationship at T⩾1300 K reported in the literature on relatively contaminated surfaces, and obtained by high-precision profilometry measurements of the decay of capillary modes associated with the wide surface scratches.

Nickel Sheets from Suspensions of the Metallic Powders in Water

Based on the optimum dispersion conditions of nickel particles in water, metal sheets are processed by tape casting of the aqueous slurries. Binder removal and oxidation competition are studied in green tapes by thermogravimetric analysis. Sintering process under reductive atmosphere is studied by dilatometry. Finally close to theoretical density (- 99% th) nickel tapes with thickness of around 500 μm is obtained.

Textured nickel tapes prepared from commercially available material

Abstract Textured Ni tapes were fabricated from commercially available nickel pellets (98.5% Ni). Ingots produced by a melt process were cold rolled to 150–400 μm thick tapes. Texturing was achieved by annealing in a reducing atmosphere (Ar + 6.5% v/v H2). Sharp cubic biaxial textured Ni tapes were obtained by thermal treatment at 1000°C for 2 hours in a reducing atmosphere. The tapes were characterized by scanning electron microscopy, X-ray diffraction and by electron backscattering diffraction. The tensile strength, the thermal expansion behavior and the Vickers hardness for the cold rolled tapes and for the heat-treated tapes were measured.

Pre-oxidized cube textured nickel tapes for YBa 2Cu 3O x coated conductors

A homogeneous nickel oxide film epitaxially grown on cube textured nickel tapes was prepared as a first buffer layer for subsequent buffer and YBa 2Cu 3O x (YBCO) layer depositions. The nickel oxide film was produced under growth conditions of surface oxidation epitaxy (SOE). The preparation of homogeneous oxide films by SOE with a high texture quality and without disturbing columnar oxide growth succeeded on micro-alloyed nickel tapes. Cerium, yttrium and silver are proven beneficial elements for micro-alloying in this respect. In silver doped metallic substrates, the cube oriented grains were produced with an increased grain aspect ratio, which was transferred to the SOE nickel oxide. Increased transport currents in the YBCO coatings were measured in the longitudinal direction of the tapes, which were coated with an additional system of buffer layers. The critical current density reached up to J c = 2.35 MA/cm 2 at 77 K in self field.

Elongated grains in textured substrate tapes and their effect on transport currents in superconductor layers

The development of cube textured flexible metallic substrate tapes is of basic interest for the economic production of YBa2Cu3Ox (YBCO) coated superconductors. Nickel tapes microalloyed with silver were prepared with the specific feature of an elongated grain structure. Cube textured NiO films were grown by surface oxidation epitaxy on these tapes retaining the elongated grains. Further, buffer layers and YBCO were deposited thereon. The YBCO layer transports an up to four times higher critical current density (Jc=2.35MA∕cm2) in the direction of grain elongation compared to the transversal one (Jc=0.55MA∕cm2).

MOCVD of Buffer Layers and Superconducting Layers on Moving Textured Nickel Tapes

Buffer layers and YBCO have been continuously deposited on textured Ni5%W tapes in a reel-to-reel MOCVD system. The buffer layers were perovskites with the composition (AA')(BB')O/sup 3/ (A, A'=La, Sr, Ca, Ba and B, B'=Cr, Mn, Fe, Co, Ni). The buffer layers were well textured with in-plane FWHM down to 5.5/spl deg/ and out-of-plane FWHM down to 2.2/spl deg/.

Effect of silver on cube texture formation in nickel substrate tapes

The effect of silver in pure nickel on the quality of the primary recrystallization cubetexture was investigated after intense cold rolling and annealing. Texture sharpness andthermal stability in the nickel tapes could be improved by micro-alloying with silver in therange of 100–500 at. ppm Ag. The sharpest cube texture was observed for theNi + 100 at. ppm Ag materialafter annealing at 550 °C (FWHM(111) = 4.4°). Further, the nickel oxide layer grown thereon had a sharp cube texture rotated by45° relative to the metallic substrate. Grain boundaries showed a typical zigzag image and thegrain form was fractal-like.

Development and evolution of biaxial texture of rolled nickel tapes by ion beam bombardment for high Tc coated conductors

High quality YBa 2Cu 3O 7 − x films on metallic substrates with high critical current densities well over 10 6 A/cm 2 can be prepared by the rolling assisted biaxially textured substrates (RABiTS) method. Nickel or its alloys have been used as biaxially textured substrates formed through a specific rolling and high temperature annealing procedures. In this paper, we report a newly developed process for developing biaxial texture in rolled Ni tape by argon ion beam bombardment. It is named the ion-beam structure modification (ISM) process. In the ISM processed Ni foils, X-ray diffraction ω scans showed the full width-half maximum (FWHM) value of the (2 0 0) peak was 5.7°. And the electron back scattering diffraction (EBSP) analysis based on scanning electron microscopy showed good {1 0 0} 〈0 0 1〉 cubic orientation and the mean grain size was determined as about 25 μm. The texture evolution of rolled Ni foils during ISM process is reported also. For ISM process, local temperature elevation and distribution arises from the ion bombardment, coupled with anisotropic incident ion penetration and propagation as a result of channeling effects in the metal lattice, are expected to play the major roles in the development of grain reorientation in the Ni foil. Due to the simplicity and efficiency of the ISM process, the technique shows a great promise for application in the industrial scale production of long-lengths of superconductor tapes.

Textured CeO/sub 2/ thin films on nickel tape by sol-gel process

Cerium oxide (CeO/sub 2/) is one of the preferred buffer layer for fabrication of coated conductors, especially when e-beam evaporation technique is used for YBCO processing. Therefore, processing of CeO/sub 2/ buffer layers has been extensively studied by several vacuum deposition techniques. However, a nonvacuum process is desired for fabrication of coated conductors to make coated conductors widely available in the market. In order to develop a nonvacuum process for fabrication of coated conductors, we fabricated textured cerium oxide (CeO/sub 2/) buffer layers on biaxially textured-Ni [100] substrates by sol-gel process. The solution was prepared from metal-organic precursor, Cerium 2,4-pentanedionate, and was deposited on the Ni substrates using a reel-to-reel sol-gel dip coating system. The textured films were annealed at 1150 /spl deg/C for 10 min under 4% H/sub 2/-Ar gas flow. Extensive texture analysis has been done to characterize the texture of CeO/sub 2/ buffer layers. X-ray diffraction (XRD) of the buffer layer showed strong out-of-plane orientation on Ni tape. The CeO/sub 2/ [111] pole figure indicated a single cube-on-cube textured structure. The omega and phi scans revealed good out-of-plane and in-plane alignments. The full-width-at-half-maximum (FWHM) values of omega and phi scans of CeO/sub 2/ films were 6.47/spl deg/ and 7.26/spl deg/, respectively. ESEM micrographs of the CeO/sub 2/ films revealed pinhole free, crack-free and dense microstructures.

Characteristic of long nickel tape for YBCO coated conductor prepared by electrodeposition

Electrodeposition method has been applied to reduce the thickness of biaxially textured Ni tape for YBCO coated conductor. The electrodeposition method can be an alternative way to the thermomechanical method, which is commonly used to fabricate a long biaxially textured substrate. This method not only has many advantages from the industrial point of view but also can improve the value of the J/sub e/ of coated conductor by reducing the thickness of Ni tape. In this work, a chemically stable cathode drum material was determined and Ti grade-2 is adequate for cathode drum materials. 20 cm long Ni tape with the thickness of 50 /spl mu/m has been prepared. X-ray /spl phi/-scan and /spl omega/-scan as a function of length were measured for Ni tape. The results showed that the average in-plane texture and out-of-plane texture are estimated to be 23.4 /spl plusmn/ 7.5/spl deg/ and 8.2 /spl plusmn/ 0.7/spl deg/ respectively.

MOCVD techniques for the production of coated conductors

New deposition techniques are used for MOCVD of YBCO-, buffer- and protective layers in a reel to reel system. This system consists of three tape reactors and evaporators. So it is possible to deposit the superconductor, the buffer layer and a protective layer in situ in one vacuum system. The operativeness of the reactors were tested separately. In the YBCO reactor superconducting films have been deposited with critical current densities over 1 MA/cm/sup 2/ at 77 K on moved textured Nickel tapes at a transport velocity of 4 m/h. Textured Ni substrates were coated in the buffer layer reactor with CeO/sub 2/ and in first experiments a Ag layer was deposited by MOCVD onto the YBCO film.

Formation of Large Highly Textured Crystalline Si Film on SiO[sub 2

Amorphous silicon (a-Si) films deposited on oxidized silicon wafers were crystallized to a highly textured form using contact printing of rolled and annealed nickel tapes. Crystallization was achieved by first annealing the a-Si film in contact with Ni tape at 600°C for 20 min in a flowing forming gas (90% N 2 , 10% H 2 ) environment, then removing the Ni tape and further annealing the a-Si film in vacuum for 2 h at 600°C. A needle-like morphology of the crystallization front typical of NiSi 2 mediated crystallization was observed. All needles, regardless of their points of origin, belonged to the same (111) family of directions except for the presence of twins and/or type A-B formations, leading to formation of nearly single crystalline regions up to ∼20 μm in radius that have their crystal axes oriented the same way in all three directions. Furthermore, the orientational relation between Si grains and Ni tape is observed to be Si ∥Νι .