Microstructure and Property of Nickel Electroformed Using Rotating Cathode in Hard Particles

2006 ◽  
Vol 315-316 ◽  
pp. 686-690
Author(s):  
Z.W. Zhu ◽  
Di Zhu
Keyword(s):  
Surface Morphology ◽  
Current Density ◽  
Traditional Method ◽  
Xrd Analysis ◽  
Novel Technique ◽  
Hard Particles ◽  
Nickel Deposits ◽  
Current Densities ◽  
And Performance ◽  
Microstructure And Performance

Nickel deposits were electroformed by a novel technique, in which the mandrel rotated in hard particles (such as ceramic beads) filling between the electrodes. The microstructure and microhardness of the deposit were studied by means of SEM, XRD analysis in contrast with the traditional method. The effects of current densities on the surface morphology and microhardness of the deposit were also studied. The results showed that the polishing, impacting and disturbing of hard particles during electrodepositing could affect the microstructure and performance of the deposits. The grains were substantially refined, the preferred orientation of (200) face weakened and the microhardness significantly increased. Moreover, the presented technique could use higher current density and produce bright and smooth deposits.

Influence of Nano Al2O3 Particles on Morphology and Microstructure of Cu-Al2O3 Composite Coating by Jet Electrodeposition

2018 ◽  
Vol 764 ◽  
pp. 164-173 ◽  
Author(s):  
Hui Fan ◽  
Man Liu ◽  
Yang Pei Zhao ◽  
Shan Kui Wang
Keyword(s):  
Surface Morphology ◽  
Composite Coating ◽  
Current Density ◽  
Steel Substrate ◽  
Metal Layer ◽  
Xrd Analysis ◽  
304 Stainless Steel ◽  
Al2o3 Nanoparticles ◽  
Jet Electrodeposition ◽  
Al2o3 Particles

Jet electrodeposition process is a very promising method in fabricating metal matrix composites reinforced with ceramic particles. In use of this method, insoluble particles suspended in an electrolytic bath are impinged onto and embedded in a growing metal layer. This paper is focused on the investigations of the copper matrix nanocomposite coatings with hard Al2O3 nanoparticles, electrochemically deposited from jet-circulated baths on 304 stainless steel substrate. The Cu-Al2O3 composite coating was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The effects of electrolyte jet velocity, current density, addition amount of Al2O3 in the electrolyte were analyzed on the microstructure change, surface morphology change as well as codeposited content of Al2O3 particles in the composite coating. It was found that increasing content of Al2O3 particles in electrolyte may improve composite coating surface morphology and increase the practical current density by exerting impingement effect on the cathode deposit surface, till excessive Al2O3 e.g.20g/L particles was added. Besides, appropriate amount of nanoparticles in the electrolyte also could offer grain refinement by providing nanocrystalline sized between 30~60 nm with current density in the range of 100~500 A/dm2.

Abrasive-Assisted Electroforming of Nickel on Translational Cathode

2013 ◽  
Vol 770 ◽  
pp. 145-149 ◽  
Author(s):  
Zeng Wei Zhu ◽  
Dong Wang ◽  
Jian Hua Ren
Keyword(s):  
Mechanical Properties ◽  
Current Density ◽  
Traditional Method ◽  
Coarse Structure ◽  
Electroforming Process ◽  
Nickel Deposits ◽  
Nickel Electroforming

Spherical abrasives were employed to polish the growing deposited layer during nickel electroforming process. On a translational flat cathode, nickel deposits with distinct polishing mark were obtained. It was found that the abrasive polishing can help to improve the microstructure and increase the mechanical properties of the nickel deposits. Compared with the deposits prepared with traditional method, the microstructure became more homogeneous and the microhardness increased nearly two times. The increase of current density led to coarse structure and lower microhardness.

Preparation and Performance of Micro-Arc Oxidation Ceramic Coating of Titanium Alloy in Low Current Density

2011 ◽  
Vol 335-336 ◽  
pp. 708-712
Author(s):  
Jian Jun Xi ◽  
Jun Zhao ◽  
Guo Jun Niu
Keyword(s):  
Titanium Alloy ◽  
Friction Coefficient ◽  
Surface Morphology ◽  
Current Density ◽  
Ceramic Coating ◽  
Low Power Consumption ◽  
Bipolar Pulse ◽  
Phosphate Silicate ◽  
Micro Arc Oxidation ◽  
And Performance

In this paper, Three types of electrolyte (phosphate, silicate, aluminum) are considered to make preparation for micro-arc oxidation coatings on titanium alloy by bipolar pulse MAO oxidation power with low power consumption (density of current less than 1A/dm2). Treated by micro-arc oxidation, dense micro-arc oxidation ceramic coating is formed on titanium alloy. Surface morphology and friction coefficient of MAO coating is analyzed. The research on the effect of NaF on ablation of MAO coating is prepared, which guides the configuration of the electrolyte later.

scholarly journals Effect of Current Density on Crystallographic Orientation, and Oxidation Behavior of Copper Plated on Aluminum Substrate

2020 ◽  
Vol 8 (4) ◽  
Author(s):  
Bambang Soegijono ◽  
Ferry Budhi Susetyo ◽  
Evi U. M. Situmorang ◽  
Yusmaniar
Keyword(s):  
Corrosion Resistance ◽  
Surface Morphology ◽  
Current Density ◽  
Crystallographic Orientation ◽  
Copper Ion ◽  
Copper Film ◽  
Aluminum Substrate ◽  
Sulfate Electrolyte ◽  
Current Densities ◽  
Electrochemical Surface Treatment

In this work, the electroplating of copper on an aluminum substrate without electrochemical surface treatment was investigated. Electroplating of copper on aluminum substrate was prepared from copper sulfate electrolyte bath with various current densities 1 mA/cm², 3 mA/cm², 10 mA/cm², and 40 mA/cm². The effects of current density on the samples properties were characterized using a different technique. The surface morphology, crystallographic orientation, and corrosion resistance of the Copper film were analyzed using a scanning electron microscope, energy dispersive spectroscopy (SEM-EDS), X-ray diffractometer (XRD), and potentiostat. The samples' surface morphology is changed with different current densities because nucleation is driven by transferring the copper ion rate onto the aluminum substrate. The Cu-10 sample exhibits (111) peak higher and the best corrosion resistance than other samples. Moreover, Cu-1 samples have shifted to positive corrosion voltage (Ecorr) than the other samples.

Facet Topography and Dislocation Structure as a Possible Source for Electrical Heterogeneity in [001] TILT Bicrystals of YBa2Cu3O7-δ

1996 ◽  
Vol 54 ◽  
pp. 338-339
Author(s):  
I-Fei Tsu ◽  
D.L. Kaiser ◽  
S.E. Babcock
Keyword(s):  
Grain Boundary ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Electromagnetic Properties ◽  
Length Scale ◽  
Density Values ◽  
Current Densities ◽  
Applied Fields ◽  
A Current

A current theme in the study of the critical current density behavior of YBa2Cu3O7-δ (YBCO) grain boundaries is that their electromagnetic properties are heterogeneous on various length scales ranging from 10s of microns to ˜ 1 Å. Recently, combined electromagnetic and TEM studies on four flux-grown bicrystals have demonstrated a direct correlation between the length scale of the boundaries’ saw-tooth facet configurations and the apparent length scale of the electrical heterogeneity. In that work, enhanced critical current densities are observed at applied fields where the facet period is commensurate with the spacing of the Abrikosov flux vortices which must be pinned if higher critical current density values are recorded. To understand the microstructural origin of the flux pinning, the grain boundary topography and grain boundary dislocation (GBD) network structure of [001] tilt YBCO bicrystals were studied by TEM and HRTEM.

Electron-beam damage of oxides at high current densities

1989 ◽  
Vol 47 ◽  
pp. 634-635
Author(s):  
M. R. McCartney ◽  
J. K. Weiss ◽  
David J. Smith
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Current Density ◽  
Transition Metal Oxides ◽  
Time Resolved ◽  
Rapid Acquisition ◽  
Resolution Electron ◽  
Current Densities ◽  
Electron Stimulated Desorption ◽  
Channel Analyzer

It is well-known that electron-beam irradiation within the electron microscope can induce a variety of surface reactions. In the particular case of maximally-valent transition-metal oxides (TMO), which are susceptible to electron-stimulated desorption (ESD) of oxygen, it is apparent that the final reduced product depends, amongst other things, upon the ionicity of the original oxide, the energy and current density of the incident electrons, and the residual microscope vacuum. For example, when TMO are irradiated in a high-resolution electron microscope (HREM) at current densities of 5-50 A/cm2, epitaxial layers of the monoxide phase are found. In contrast, when these oxides are exposed to the extreme current density probe of an EM equipped with a field emission gun (FEG), the irradiated area has been reported to develop either holes or regions almost completely depleted of oxygen. ’ In this paper, we describe the responses of three TMO (WO3, V2O5 and TiO2) when irradiated by the focussed probe of a Philips 400ST FEG TEM, also equipped with a Gatan 666 Parallel Electron Energy Loss Spectrometer (P-EELS). The multi-channel analyzer of the spectrometer was modified to take advantage of the extremely rapid acquisition capabilities of the P-EELS to obtain time-resolved spectra of the oxides during the irradiation period. After irradiation, the specimens were immediately removed to a JEM-4000EX HREM for imaging of the damaged regions.

scholarly journals Hard Coating Materials Based on Photo-Reactive Silsesquioxane for Flexible Application: Improvement of Flexible and Hardness Properties by High Molecular Weight

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1564
Author(s):  
Jong Tae Leem ◽  
Woong Cheol Seok ◽  
Ji Beom Yoo ◽  
Sangkug Lee ◽  
Ho Jun Song
Keyword(s):  
Molecular Weight ◽  
Surface Morphology ◽  
High Molecular Weight ◽  
Sol Gel ◽  
Xrd Analysis ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Coating Materials ◽  
Pencil Hardness ◽  
Coated Film ◽  
Flexible Application

EPOSS of polyhedral oligomeric silsesquioxanes (POSS) mixture structure and LPSQ of ladder-like polysilsesquioxane (LPSQ) structure were synthesized via sol–gel reaction. EPSQ had a high molecular weight due to polycondensation by potassium carbonate. The EPSQ film showed uniform surface morphology due to regular double-stranded structure. In contrast, the EPOSS-coated film showed nonuniform surface morphology due to strong aggregation. Due to the aggregation, the EPOSS film had shorter d-spacing (d1) than the EPSQ film in XRD analysis. In pencil hardness and nanoindentation analysis, EPSQ film showed higher hardness than the EPOSS film due to regular double-stranded structure. In addition, in the in-folding (r = 0.5 mm) and out-folding (r = 5 mm) tests, the EPSQ film did not crack unlike the EPOSS coated film.

scholarly journals Effect of Plating Current Density on the Ball-On-Disc Wear of Sn-Plated Ni Coatings on Cu Foils

Coatings ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 56
Author(s):  
Ashutosh Sharma ◽  
Byungmin Ahn
Keyword(s):  
Current Density ◽  
Wear Loss ◽  
Wear Properties ◽  
Friction Behavior ◽  
Track Geometry ◽  
Cu Substrates ◽  
Current Densities ◽  
The Impact ◽  
Sliding Distance ◽  
Ball On Disc

Metallic and alloyed coatings are used widely in several decorative and technology-based applications. In this work, we selected Sn coatings plated on Cu substrates for joining applications. We employed two different plating baths for the fabrication of Sn and Ni coatings: acidic stannous sulfate for Sn and Watts bath for Ni layer. The plating current densities were varied from 100–500 mA/cm2. Further, the wear and friction behavior of the coatings were studied using a ball-on-disc apparatus under dry sliding conditions. The impact of current density was studied on the morphology, wear, and coefficient of friction (COF) of the resultant coatings. The wear experiments were done at various loads from 2–10 N. The sliding distance was fixed to 7 m. The wear loss was quantified in terms of the volume of the track geometry (width and depth of the tracks). The results indicate that current density has an important role in tailoring the composition and morphology of coatings, which affects the wear properties. At higher loads (8–10 N), Sn coatings on Ni/Cu had higher volume loss with a stable COF due to a mixed adhesive and oxidative type of wear mechanism.

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