Electroplating Methods Research Articles

Analysis of hydrogen embrittlement in zinc electroplating

Electrodeposition is the method of plating metal into another by hydrolysis generally to protect against corrosion of metal. In Zinc Electroplating, Zinc is deposited on steel, where Zinc acts as a sacrificial element that enhances Steel’s life. The zinc electroplating methods are mostly affected by process parameters such as current, temperature, voltage, etc. Hydrogen is absorbed in the plated Zinc layer and later it causes cracking, which is known as hydrogen embrittlement. Hydrogen De Embrittlement is a process that removes Hydrogen. Various test methods are used to qualify a part after hydrogen de-embrittlement. One of them, the Silicon oil test was used to detect it earlier and now we have used paraffin oil for the same, thus making it cost-efficient.

High-performance paper-based humidity sensors with Nafion/AgNWs hybrid electrodes.

In the past decade, the development of medical health and human-computer interfaces has put forward requirements for the non-contact application of flexible electronics. Among them, flexible humidity sensors play an important role in the field of non-contact sensing by virtue of their rapid response to humidity changes. In this paper, a flexible paper-based humidity sensor with high performance was fabricated by embedded Au@AgNWs electrodes on filter paper through spraying and electroplating (EP) methods. Benefitting from the moisture-sensitive properties of the paper and the tight integration of the electrodes into the filter paper, the sensor shows the humidity monitoring range of 33-100% RH, large response value of I/I0 = 1958, excellent linearity of R2 = 0.99662 and hysteresis performance under the low excitation voltage of only DC 1 V. In addition, the good biocompatibility of the paper-based humidity sensor endows it with multifunctional applications for breath detection, non-contact applications and food security monitoring. Easy access to raw materials and convenient preparation methods of this work provide new ideas for the development and commercialization of flexible humidity sensors.

Electroplated core\u2013shell nanowire network electrodes for highly efficient organic light-emitting diodes

In this study, we performed metal (Ag, Ni, Cu, or Pd) electroplating of core–shell metallic Ag nanowire (AgNW) networks intended for use as the anode electrode in organic light-emitting diodes (OLEDs) to modify the work function (WF) and conductivity of the AgNW networks. This low-cost and facile electroplating method enabled the precise deposition of metal onto the AgNW surface and at the nanowire (NW) junctions. AgNWs coated onto a transparent glass substrate were immersed in four different metal electroplating baths: those containing AgNO3 for Ag electroplating, NiSO4 for Ni electroplating, Cu2P2O7 for Cu electroplating, and PdCl2 for Pd electroplating. The solvated metal ions (Ag+, Ni2+, Cu2+, and Pd2+) in the respective electroplating baths were reduced to the corresponding metals on the AgNW surface in the galvanostatic mode under a constant electric current achieved by linear sweep voltammetry via an external circuit between the AgNW networks (cathode) and a Pt mesh (anode). The amount of electroplated metal was systematically controlled by varying the electroplating time. Scanning electron microscopy images showed that the four different metals (shells) were successfully electroplated on the AgNWs (core), and the nanosize-controlled electroplating process produced metal NWs with varying diameters, conductivities, optical transmittances, and WFs. The metal-electroplated AgNWs were successfully employed as the anode electrodes of the OLEDs. This facile and low-cost method of metal electroplating of AgNWs to increase their WFs and conductivities is a promising development for the fabrication of next-generation OLEDs.

MAKING PROTOTYPE OF ELECTRO PLATING EQUIPMENT FOR HOME INDUSTRYOME INDUSTRI

Corrosion is an electrochemical reaction process that is natural and takes place by itself, corrosion cannot be prevented or stopped but can only be controlled using the Electro Plating method. Electroplating is a process that produces a thin layer of metal on top of another metal surface by electrolysis or electroplating using direct current (DC) and chemical solutions (electrolytes). The process of giving this protective layer aims to protect the metal from corrosion, in this study, will make a prototype electro plating tool for small industry or Home Industry, the completeness of the components needed to make a prototype electro plating tool is an AC transformer matic 30-50 A 12V, ampere meter, volt meter, fuse and switch, then nickel solution serves to provide strength, metal resistance from rust and chrome solution serves to provide resistance to corrosion and gives a glossy white color so it looks better, to produce a strong coating. With the occurrence of the anode, cathode, and electrolyte solution which are used entirely as related to coating materials, especially metals are illustrated as, the cathode can be interpreted as the workpiece to be coated, connected to the negative pole of the electric current source and the electrolyte in the form of a solution whose molecules can be dissolved. in water and decomposes into positively or negatively charged particles and the deposition in the process is due to the presence of ions in the electrolyte and will settle on the cathode and the process of coating the metal occursPlease write your abstract in English version here.

Study on Electrical Explosion Properties of Cu/Ni Multilayer Exploding Foil Prepared by Magnetron Sputtering and Electroplating.

The purpose of this study was to investigate the effects of the microstructure and properties of Cu/Ni multilayer films prepared by magnetron sputtering and electroplating on the electrical explosion performance of the films. In this study, Cu/Ni multilayer films of the same thickness were prepared by electroplating (EP) and magnetron sputtering (MS), and their morphology and crystal structure were characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). XRD was used to observe the crystal structure and size of the samples. In addition, the Cu/Ni multilayer film was etched into the shape of a bridge, and the electric explosion phenomenon in the same discharge circuit of the multilayer foil obtained by the two preparation processes was tested by an electric explosion performance test system. The resistance–time curve and the energy–resistance curve during the electric explosion process were analyzed and calculated. The results showed that compared with the multilayer film prepared by the MS method, the crystal size of the multilayer film prepared by the EP method is smaller and the interface of Cu/Ni is clearer. In the electric explosion experiment, the MS samples had earlier burst times, larger peak resistances, smaller peak energies and higher ionization voltages. Through observation of the morphology of the samples after the electric explosion and combination with gas ionization theory, the internal influencing factors of the peak voltage and the relative resistance of the two samples were analyzed. The influence of the multilayer film mixing layer thickness on the sample energy conversion efficiency was analyzed by modeling the microstructure of the multilayer film exploding foil and electric heating. The results show that the thicker the mixing layer is, the more energy is distributed on the Ni, the faster the resistance increases, and the higher the energy conversion efficiency.

Oxidation and electrical behaviour of direct and pulse current electroplated cobalt coatings on Crofer22APU stainless steel interconnect

ABSTRACTResearches keep on to improve oxidation resistance and electrical conductivity of solid oxide fuel cell (SOFC) interconnects. In this work, Co coating was applied on Crofer22APU ferritic stainless steel interconnect by pulse current electrodeposition (PCE) method. The surface and cross-section of the samples were characterised by the SEM-EDX and XRD techniques. Investigations showed that pulse current resulted in decrease of grain size, roughness and porosity of Co deposits compared to the Co coating formed by the direct current electroplating (DCE) method. The steels were exposed to air at 800°C for 500 h and their oxidation rates were calculated. Oxidation rates were decreased for PCE-Co coated samples relative to for DCE-Co coated and uncoated samples. Electrical conductivity of the samples as a function of the temperature was also evaluated in air at 800°C. The PCE-Co coated Crofer22APU exhibited electrical conductivity as high as 54.64 S cm2 at 800°C.

Comparative performances of Ni-SiC composite coatings deposited by conventional and brush electroplating

SiC particles are known as reinforced materials used to improve the coating’s properties and performances. In this paper, Ni - SiC composite coatings were deposited by conventional electroplating from sulfate-chloride bath, and brush electroplating methods from modified chloride bath with different dispersed SiC contents. The plating conditions were investigated and the process’ parameters were defined through electrochemical technique. Scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and micro-hardness test were used to clarify the effect of SiC content on coating’s properties and performances. The hardness of brush electrodeposit reached the highest value of 525 HV when the concentration of SiC in the plating solution was 4 g/L, while the hardness of conventional electrodeposit was only 389.3 HV when the plating bath contained 20 g/L SiC. The characterized results show clear advantages of brush electroplating compared to the conventional method to form the coating with high micro-hardness.

Preparation of Metal-Gr Composite Coatings Via Electro-Plating for High Corrosion Resistances

1) Preparation of Fe-Gr composite coating via DC electro-plating for high performances. In this work, the iron-graphene (Fe-Gr) composite layer was prepared by using an electro-plating method. The performance of the composite was varied with the concentrations of GO in the electrolyte. The layer’s microstructures were systematically characterized by SEM, TEM, Raman, FT-IR, and the micro-hardness and its corrosion resistance were evaluated for getting desired properties. The experimental results revealed that: 1) the Gr could be scattered homogeneously in the Fe layer when dispersible graphene oxide (GO) was added in the electrolyte; 2) comparing with pure Fe layer, the micro-hardness and corrosion resistance of the Fe-Gr composite layer were greatly enhanced; 3) it was found that there was an optimal GO addictive amount (0.4 g/L) in the electrolyte, which increased the properties involving the micro-hardness up to HV 248, 2.07 times higher than that of pure iron layer(HV 120); 3.75 times of anti-corrosion rate(0.1353 mmy-1) and 5.38 times of the charge transfer resistance(1456 /(Ω·cm2) higher than that of pure iron layer(0.5076 mmy-1, 270.5 /(Ω·cm2). 2) Preparation of Zn-Gr composite coating via pulse reverse electro-plating for high corrosion resistances. In this work, a kind of the Zn-Gr composite layer is successfully prepared on iron substrate via pulse reverse electro-plating method from a chloride aqueous solution. The experimental results revealed that: 1) By adding GO in the electrolyte, Gr sheets can be incorporated homogenously in the Zn plating layer during electro-plating, and the reduction from GO into Gr occurs due to the Zn and GO co-deposition. 2) Due to increasing of the nucleation sites, Gr incorporation changes the growth mechanism of Zn crystal, i.e., makes the main preferred orientations from (112) and (101) crystal planes in the pure Zn layer into (103), (102) and (110) planes in the Zn-Gr composite layers. 3) As a corrosion protection barrier layer, Gr sheets play an important role on the corrosion resistance of the Zn-Gr composite plating layers in simulated seawater environment. The highest corrosion resistant properties occur in an optimal range 0.3 – 0.5g/L GO adding amount in the electrolyte, at which the corrosion current density just be a hundredth comparing with that of pure Zn layer. 4) The present method for preparing Zn-Gr composite, with advantages of simple, controllable, scalable, etc., is likely to be industrialized.

Oxidation Resistance of Modified Aluminide Coatings

The application of protective aluminide coatings is an effective way to increase the oxidation resistance of the treated parts and prolongs their lifetime. The addition of small amount of noble metals (platinum or palladium) or reactive elements such as: hafnium, zirconium, yttrium and cerium has a beneficial effect on oxidation behavior. This beneficial effect includes an improvement of adhesion of alumina scales and reduction of oxide scale growth rate. Platinum and hafnium or zirconium modified aluminide coating were deposited on pure nickel using the electroplating and CVD methods. The coatings consisted of two layers: an outer, β-NiAl phase and the interdiffusion γ’-Ni3Al phase. Palladium dissolved in the whole coating, whereas hafnium and zirconium formed inclusions on the border of the layers. Samples were subjected to cyclic oxidation test at 1100 °C for 200h. Oxidation resistance of the palladium, Hf+Pd and Zr+Pd modified coatings deposited on pure nickel does not differ significantly, but is better than the oxidation resistance of the non-modified one.

Preparation of Fe - Gr composite layer via DC electro-plating for high performances

In this article, the iron-graphene (Fe-Gr) composite layer was prepared by using an electro-plating method. The performance of the composite was varied with the concentrations of GO in the electrolyte. The layer's microstructures were systematically characterized by SEM, TEM, Raman, FT-IR, and its micro-hardness and corrosion resistance were evaluated for getting desired properties. The experimental results revealed that: 1) the Gr could be scattered homogeneously in the Fe layer when dispersible graphene oxide (GO) was added in the electrolyte; 2) comparing with pure Fe layer, the micro-hardness and corrosion resistance of the Fe-Gr composite layer were greatly enhanced; 3) it was found that there was an optimal GO adding amount (0.4 g/L) in the electrolyte, which increased the properties involving the micro-hardness up to HV 248, 2.07 times higher than that of pure iron layer (HV 120); 3.75 times of anti-corrosion rate (0.1353 mmy−1) and 5.38 times of the charge transfer resistance (1456 Ω cm2) higher than that of pure iron layer (0.5076 mmy−1, 270.5 Ω cm2).

Flexible and Transparent Graphene Electrode Architecture with Selective Defect Decoration for Organic Light‐Emitting Diodes

AbstractGraphene produced by chemical vapor deposition (CVD) has attracted great interest as a transparent conducting material, due to its extraordinary characteristics such as flexibility, optical transparency, and high conductivity, especially in next‐generation displays. Graphene‐based novel electrodes have the potential to satisfy the important factors for high‐performance flexible organic light‐emitting diodes (OLEDs) in terms of sheet resistance, transmittance, work function, and surface roughness. In this study, flexible and transparent graphene electrode architecture is proposed by adopting a selective defect healing technique for CVD‐grown graphene, which results in several benefits that produce high‐performance devices with excellent stabilities. The proposed architecture, which has a multi‐layer graphene structure treated by a layer‐by‐layer healing process, exhibits significant improvement in sheet resistance with high optical transparency. For improving the charge transport property and mechanical robustness, various defect sites of the CVD‐grown graphene are successfully decorated with gold nanoparticles through a simple electroplating (EP) method. Further, a graphene‐based OLED device that integrates the proposed electrode architecture on flexible substrates is demonstrated. Therefore, this architecture provides a new strategy to fabricate graphene electrode in OLEDs, extending graphene's immense potential as an advanced conductor toward high‐performance, flexible, and transparent displays.

Low Temperature Soldering Surface-Mount Electronic Components with Hydrogen Assisted Copper Electroplating

ABSTRACTCopper growth for the development of electroplating technique as a low-temperature soldering procedure represents a useful method for the formation of metal deposits, allowing modification of the thickness and morphology of the soldering joints. The approach is particularly useful for soldering electronic components to a plastic 3D printed substrate. To accelerate the soldering process hydrogen assisted electroplating (HAE) method was employed at room temperature. The experiments were designed by making a small electrochemical cell around the gap on a printed circuit board (PCB) or a 3D printed conductive track. During the experiment, water electrolysis was observed, which released hydrogen bubbles. The hydrogen bubbles caused the structure of the electroplated layer to be more porous, but with a similar conductivity as solid copper and a remarkable mechanical strength suitable for use as interconnects on an electronic circuit. Our electrochemical data and video recorded images show a fast and reliable copper electrodeposition in less than 1 minute. The morphology of copper deposits on a 3D printed structure was studied with the scanning electron microscopy (SEM). A reliable soldering process was demonstrated for a surface mount light emitting diode (LED) on a PCB. Further experiments are required to optimize the soldering process for faster and more reliable electroplating, particularly for 3D printed substrates.

Influence of Graphene Oxide Content on the Zn-Gr Composite Layer Prepared by Pulse Reverse Electro-plating

The Zinc (Zn)-graphene (Gr) composite layer was prepared successfully by using a pulse reverse electro-plating method on the iron substrate. Effect of GO content in the electrolyte on the microstructures of the composite layer and the corrosion behaviors in the 3.5 wt% NaCl solution were also investigated in detail by using scanning electron microscope (SEM), X-Ray Diffraction (XRD) and a series of electrochemical measurements. The results revealed that: 1) GO can be reduced into Gr during the co-deposition of electro-plating; 2) adding GO in the electrolyte changed the Zn growth mechanism in the composite layer, i.e., gradually transforming from the main preferred orientations of (112) and (101) crystal planes into (103), (102) and (110) planes 3) there is an optimal GO adding amount in a range 0.3–0.5g/L in the electrolyte, at which the Zn-Gr composite layer exhibited the highest corrosion resistance and corrosion current density just be a hundredth comparing with that of pure Zn layer in simulated seawater environment; 4) the Zn-Gr composite layer is of a strong adhesion with the substrate. The present work is expected to provide basic data for future practical applications in galvanized steel used for corrosion environment.

Nickel/sulfur composite electroplated nickel foams for the use as 3D cathode in lithium/sulfur batteries – A proof of concept

In this work, a composite electroplating method of manufacturing organic binder and conductive carbon free electrode materials is applied on nickel foam substrates, used as 3D current collector. Thereby, sulfur particles (d50 = 24µm) are functionalized with polythiophene (layer thickness 100–200nm) and brought to the surface of the nickel foam by means of composite electroplating while using nickel as a mechanically stable and electrically well conducting binding matrix for sulfur (Ni layer thickness around the sulfur particles < 1µm). Therefore, organic nonconducting binders such as PVDF and conducting additives such as carbon are redundant. The method of composite electroplating ensures high sulfur loading with additional surface structuring, while keeping all pores accessible to the battery electrolyte. The naturally high surface of the metal foam is thereby further increased, which helps to decrease local current densities in the battery application. Cross-section SEM micrographs and CT images show that the functionalized sulfur particles are uniformly and densely distributed throughout the nickel foam. A battery capacity of about 300mAhg−1sulfur over 100 cycles at a current density of 1mAcm−2 (0.167C) for a cathode containing 3.57mgcm−2 sulfur is achieved. With an additional 50nm thin NiSx alloy coating, the utilization of sulfur is improved by 250–300% (a battery capacity of about 800mAhg−1sulfur over 100 cycles at a current density of 1mAcm−2 (0.162C) for a cathode containing 3.68mgcm−2 sulfur is achieved). Furthermore, a high reversibility and rate capability is found when cycled between 0.1 and 1C, respectively. A stable coulombic efficiency of about 100% is achieved.

Prospects of Galvanic Sludge Recycling

The article analyzes galvanic sludge recycling methods; development prospects are outlined; recycling in the electroplating industry is considered in terms of environment protection. Actual methods of galvanic sludge reuse are systematized. The author suggests areas for development of less hazardous electroplating methods.

The effects of silver coating on friction coefficient and shear bond strength of steel orthodontic brackets.

Aims of the present study was to measure frictional resistance between silver coated brackets and different types of arch wires, and shear bond strength of these brackets to the tooth. In an experimental clinical research 28 orthodontic brackets (standard, 22 slots) were coated with silver ions using electroplate method. Six brackets (coated: 3, uncoated: 3) were evaluated with Scanning Electron Microscopy and Atomic Force Microscopy. The amount of friction in 15 coated brackets was measured with three different kinds of arch wires (0.019 × 0.025-in stainless steel [SS], 0.018-in stainless steel [SS], 0.018-in Nickel-Titanium [Ni-Ti]) and compared with 15 uncoated steel brackets. In addition, shear bond strength values were compared between 10 brackets with silver coating and 10 regular brackets. Universal testing machine was used to measure shear bond strength and the amount of friction between the wires and brackets. SPSS 18 was used for data analysis with t-test. SEM and AFM results showed deposition of a uniform layer of silver, measuring 8-10 μm in thickness on bracket surfaces. Silver coating led to higher frictional forces in all the three types of arch wires, which was statistically significant in 0.019 × 0.025-in SS and 0.018-in Ni-Ti, but it did not change the shear bond strength significantly. Silver coating with electroplating method did not affect the bond strength of the bracket to enamel; in addition, it was not an effective method for decreasing friction in sliding mechanics.

Characteristic of Through Silicon Via’s Seed Layer Deposition and Via Filling

As continued scaling becomes increasingly difficult, 3D integration has emerged as a viable solution to achieve higher bandwidths and good power efficiency. 3D integration can be defined as a technology involving the stacking of multiple processed wafers containing integrated circuits on top of each other with vertical interconnects between the wafers. This type of 3D structure can improve performance levels, enable the integration of devices with incompatible process flows, and reduce form factors. Through silicon vias (TSVs), which directly connect stacked structures die-to-die, are an enabling technology for future 3D integrated systems. TSVs filled with copper using an electro-plating method are investigated in this study. DC and pulses are used as a current source for the electro-plating process as a means of via filling. A TiN barrier and Ru seed layers are deposited by plasma-enhanced atomic layer deposition (PEALD) with thicknesses of 10 and 30 nm, respectively. All samples electroplated by the DC current showed defects, even with additives. However, the samples electroplated by the pulse current showed defect-free super-filled via structures. The optimized condition for defect-free bottom-up super-filling was established by adjusting the additive concentrations in the basic plating solution of copper sulfate. The optimized concentrations of JGB and SPS were found to be 10 and 20 ppm, respectively.

Lithium manganese aluminum oxide-based full Li-ion battery using carbon fibers as current collectors

Herein, Li-ion battery using carbon fibers instead of conventional aluminum/copper foils as the current collectors is assembled. To achieve the binder-free environment, LiMn0.97Al0.03O2-based fiber type cathode is prepared directly via a two-step strategy involving electroplating and hydrothermal method by forming active materials on the individual carbon fiber. Cu6Sn5-based fiber type anode is prepared directly via electroplating and subsequent heat treatment. The resulting LiMn0.97Al0.03O2|Cu6Sn5 Li-ion battery using carbon fiber as the current collector functions at about 3 V, with an initial capacity of 180 mAh g−1 (based on the cathode). The capacity retention is 90 % after 150 cycles. In particular, the battery using phosphate-modified LiMn0.97Al0.03O2-based fiber type electrode demonstrates a better cycling and high rate performance compared to the unmodified counterpart.

A new approach to control a deflection of an electroplated microstructure: dual current electroplating methods

We propose and demonstrate a simple and novel method to control the deflection in a suspended microstructure by using a dual current electroplating (DuCE) method. The key concept of this method is to divide the structure into two layers—a bottom layer and a top layer—and then apply respective current densities in electroplating to those two layers while all other conditions are kept the same. In addition to a flat structure, the direction of structure bending is freely controlled by virtue of the DuCE method. Cantilever Ni beams with a length of 400 µm, which were electroplated by the conventional single current electroplating method, bent downward with a deflection of 3.4 µm. On the contrary, by the DuCE method, cantilever beams with a length of 400 µm showed an almost flat structure as desired. (The current densities of the bottom layer, the top layer, and the ratio of the two current densities, are 0.15, 1.24 A dm−2, and 8.3, respectively.) Consequently, a nickel electroplated spiral structure with a length of 8600 µm was suspended flat with an end deflection of less than 0.7 µm (the ratio between the deflection and length is 0.007%). This work therefore represents the unprecedented ultra-long suspended microstructure with submicrometer deflection.

Evaluation of electrodeposited ternary Ni-alloys for thermal stability

Electroplating methods for ternary Ni-alloys, such as Ni-P-Fe and Ni-P-B, in a Ni sulfamate solution on the inner wall surfaces of Alloy 600 tubing have been developed in order to use them to repair steam generator tubes damaged by a variety of corrosion mechanisms, in particular, by stress corrosion cracking. In this study, the stability of their microstructures and mechanical properties were evaluated to check if they could be used for a long period of time at the operating temperature of a PWR (pressurized water reactor) in nuclear power plants. The specimens were heat treated at 325 °C and 400 °C for 10, 20 and 30 days, followed by observation of their microstructures and measurement of their microhardness and tensile property. According to the experiment results, there was no noticeable change in their microstructures or microhardness with the heat treatment temperature and time conditions used in this study. For a Ni-P-B deposit, the ultimate tensile strength (UTS) slightly increased with the heat treatment time, while their elongation decreased. In the case of a Ni-P-Fe deposit, however, its tensile property varied with the applied current density. For a Ni-P-Fe deposit plated at an applied current density of 50 mA/cm2, its UTS slightly decreased, but its elongation slightly increased with the heat treatment time. We concluded that the thermal stability of the ternary Ni-alloy deposits used in this study is good enough to be used with the materials of operating nuclear power plants.