Search

The sensitivity of zinc (Zn(II)) detection using fast-scan cyclic voltammetry (FSCV) with carbon fiber microelectrodes (CFMEs) is low compared to other neurochemicals. We have shown previously that Zn(II) plates to the surface of CFME's and we speculate that it is because of the abundance of oxide functionality on the surface. Plating reduces sensitivity over time and causes significant disruption to detection stability. This limited sensitivity and stability hinders Zn(II) detection, especially in complex matrices like the brain. To address this, we developed plasma-treated gold fiber microelectrodes (AuMEs) which enable sensitive and stable Zn(II) detection with FSCV. Typically, gold fibers are treated using corrosive acids to clean the surface and this step is important for preparing the surface for electrochemistry. Likewise, because FSCV is an adsorption-based technique, it is also important for Zn(II) to adsorb and desorb to prevent irreversible plating. Because of these requirements, careful optimization of the electrode surface was necessary to render the surface for Zn(II) adsorption yet strike a balance between attraction to the surface vs. irreversible interactions. In this study, we employed oxygen plasma treatment to activate the gold fiber surface without inducing significant morphological changes. This treatment effectively removes the organic layer while functionalizing the surface with oxygen, enabling Zn(II) detection that is not possible on untreated gold surfaces. Our results demonstrate significantly improved Zn(II) detection sensitivity and stability on AuME compared to CFME's. Overall, this work provides an advance in our understanding of Zn(II) electrochemistry and a new tool for improved metallotransmitter detection in the brain. [ABSTRACT FROM AUTHOR]

In new energy battery manufacturing, machine vision is widely used in automated assembly scenarios for key parts. To improve the accuracy and real‐time multi‐target positioning recognition of flexible thin parts, this paper proposes a multi‐level feature fusion template matching algorithm based on the Gaussian pyramid. Firstly, the algorithm constructs a Gaussian pyramid by multi‐scale image construction. Secondly, considering the image features of each layer of the pyramid, this paper uses the grey‐based Fast Normalized Matching algorithm to obtain coarse positioning coordinates on the upper layer, and the improved Linemod‐2D algorithm is applied to the bottom layer image to get accurate positioning coordinates. Finally, the positioning coordinates returned from each layer are fused to obtain the final positioning coordinate. The experimental results show that the proposed algorithm achieves excellent performance in nickel plate positioning and recognition. It exhibits satisfactory performance in nickel sheet localization and recognition. In terms of angular error, repeat accuracy, and matching speed, it competes favourably with Halcon, VisionMaster, and SCISmart. Its positioning error closely approximates that of Halcon, effectively meeting the practical production demands for high‐speed feeding and high‐precision positioning. [ABSTRACT FROM AUTHOR]

Bamboo fiber has attracted attention due to its high strength and flexibility, but it shows poor electron mobility and functionalities. In this research, phosphorus-doped flexible electrodes were constructed using bamboo fiber as the substrate, which was pretreated using sodium borohydride, followed by chemical nickel plating, and then used for urea electrocatalytic oxidation. The results showed that the bamboo fiber film provided a flexible support for nickel metal loading and a uniform and dense metal coating. Along with phosphorus self-doping, this conferred significant electrocatalytic activity to the nickel-phosphorus/bamboo fiber film (Ni–P/BFF). Notably, the electrode demonstrated an initial oxidation potential of 436.4 mV during urea oxidation. Phosphorus doping induced charge density redistribution and changed the electronic states during chemical plating, making the area around nickel atoms effective electron-trapping centers. This lowered the free energy of OH− adsorption on the surface of the conductive network in the electrolyte, which in turn lowered the onset potential and Tafel slope. These findings present a novel perspective for using biomass materials to create flexible electrodes. [Display omitted] • Eco-friendly, high-performance and low-cost flexible electrode material based on natural bamboo fiber was created. • The conductive network on bamboo fibers constitutes electron transport channels and provide electrocatalytic active sites. • Self-doping with phosphorus significantly enhanced the electrocatalytic activity, particularly for urea oxidation. [ABSTRACT FROM AUTHOR]

Nickel (Ni) is an interesting candidate for corrosion protection of copper (Cu) due to its present passive area. Ni films with larger passive areas have better corrosion protection than those with smaller ones. In the present research, Ni films were produced over Cu. A barreling apparatus was employed to support the produced films in the sulphate solution. Various spinning speeds (0, 50, and 100 rpm) were used on the barrel while it was being processed. Several investigations were conducted, such as deposition rate, current efficiency, surface morphology, phase, film thickness, crystallographic orientation, and electrochemical properties. Increased spinning speed resulted in a decrease in the deposition rate, current efficiency, grain size, thickness, crystallite size, and exchange current density. Compared to a higher spinning speed, the decrease in spinning speed caused an increase in the oxygen content, surface roughness, and micro-strain. The higher speed of the barrel apparatus resulted in a lower corrosion rate Ni film of 0.147 mmpy. Moreover, the lower speed of the barrel apparatus resulted in a higher exchange current density Ni film of 0.997 A/cm². [ABSTRACT FROM AUTHOR]

Copper plating on graphite surfaces is employed as an effective strategy to enhance the wettability between Cu and graphite, which is otherwise inadequate. To achieve a uniformly coated Cu layer on graphite surfaces, this study utilized rotational electroless plating. Subsequently, the effects of CuSO4 ⋅ 5H2O concentrations (10, 15, 20, and 25 g/L) and reaction solution temperatures (30, 40, 50, and 60 °C) on the uniformity and density of the Cu coating on the graphite surface were investigated. The findings reveal that variations in the concentration of the CuSO4 ⋅ 5H2O have a limited impact on the uniformity and densification of the Cu coating. Specifically, as the concentration of CuSO4 ⋅ 5H2O increases from 10 g/L to 25 g/L, there is a slight decrease in the uniformity and integrity of the Cu coating, with the density of Cu‐coated graphite powder decreasing marginally from 3.646 g/cm3 to 6.642 g/cm3. In contrast, the temperature of the reaction solution has a significant effect on the uniformity and densification of the Cu coating. With an increase in the reaction solution temperature from 30 °C to 60 °C, there is a noticeable deterioration in the uniformity and integrity of the Cu coating, with a decrease in the density of Cu‐coated graphite powder from 3.653 g/cm3 to 6.620 g/cm3. [ABSTRACT FROM AUTHOR]

Hot stamping of steel is an innovative process for producing components of higher strength with a significant weight reduction. Conventional hot stamping process is carried out at an elevated temperature in the range of 800 to 950 °C in atmospheric condition. So, a coating is a must to restrict high temperature oxidation and decarburization of the steel substrate. Majorly, Al-Si coating and Zn-based coatings are used for the purpose. However, Al-Si-based coatings are not able to provide sacrificial cathodic protection to steel substrate and the Zn-based coating suffer from the problem of microcracking. In the present study, the pre-Ni coated galvanized boron steels are investigated to understand high temperature phase transformation during austenitization step. Thermodynamic calculations along with Gleeble heat treatment experiments and coating characterizations with SEM, EDS, WDS and XRD shows initial melting of the coating. Subsequent Fe-enrichment in the coating has led to formation of BCC phase which is high melting as well as softer phase compared to Ni-Zn intermetallic. Moreover, the corrosion performance of the prior Ni coated galvanized steel has been evaluated. The presence of zinc in the coating shows sacrificial corrosion protection behavior and the Ni and Fe in the coating have further improved the corrosion rate owing to their barrier protection to the steel. [ABSTRACT FROM AUTHOR]

The greatest losses during gas transportation occur in the elements of shut-off valves, the operating parameters of which, among other things, depend on the thickness and hardness of the protective coating of the ball plugs. The study of the parameters of nickel–phosphorus and chrome coatings on ball plugs of serially produced shut-off valves, including control of their thickness and hardness, was carried out. Based on the test results, deviations in the actual parameters of coatings from the requirements of technological documentation were revealed, the necessity of their complex control was substantiated, recommendations on the choice of methods and equipment were formulated, and the main provisions of the test methodology were developed. [ABSTRACT FROM AUTHOR]

Nanocrystalline NiFe thin films of 11 μm thickness have been deposited on Cu wire using an electrochemical technique in galvanostatic mode with a sodium gluconate (SG) additive in the plating solution. The SG concentration is systematically varied from 0 g/L to 80 g/L, which results in a substantial enhancement in the soft magnetic characteristics and magnetoimpedance (MI) ratio of the plated wire across a broad frequency spectrum, specifically attributed to the optimal inclusion of SG at 55 g/L. The observed improvements in magnetic softness and MI ratio are linked to the reduction in crystalline size and surface roughness and modifications in the microstructure influenced by the SG additive in the electroplating bath. Furthermore, an equivalence between experimental impedance data and the theoretical framework based on the analytical model of circumferential permeability is outlined to extract the material parameters of the permalloy magnetic films. These extracted parameters play a pivotal role, enabling a comprehensive understanding of the variation in the MI ratio as well as circumferential permeability of the thin films as a function of the SG additive concentration in the plating bath. The intricate association observed between the MI ratio and circumferential permeability suggests that the amplification of the MI ratio resulting from the inclusion of SG is linked primarily to enhancements in circumferential permeability and the incorporation of magnetic softness. Thus, the present work offers both a theoretical and experimental framework for future research in advanced MI-based devices for magnetic sensing applications. [ABSTRACT FROM AUTHOR]

This work proposes for the first time protecting–reflecting on both sides of plated mirrors and a solution to polycarbonate surface vulnerability to weathering and scratching using tungsten disulfide (WS2) by mechanical polishing. The ability of the dynamic chemical plating (DCP) technique to deposit Ag films at the nanometer scale on a polycarbonate (PC) substrate and its characteristics to be metallized is also shown. These deposits hold significant promise for concentrated solar power (CSP) applications. Complementarily, the application of WS2 as a reflective film for CSP by mechanical polishing on smooth polycarbonate surfaces is both novel and practical. This technique is innovative and scalable without needing reactants or electrical potential, making it highly applicable in real-world scenarios, including, potentially, on-site maintenance. The effects of surface morphology and adhesion, and the reflectivity parameters of the silver metallic surfaces were investigated. Wettability was investigated because it is important for polymeric surfaces in the activation and metal deposition immediately after redox reactions. The flame technique improved wettability by modifying the surface with carbonyl and carboxyl functional groups, with PC among the few industrial polymers that resisted such a part of the process. The change in the chemical composition, roughness, and wettability of the surfaces effectively improved the adhesion between the Ag film and the PC substrate. However, it did not significantly affect the adhesion between PC and WS2 and showed its possible implementation as a first surface mirror. Overall, this work provides a scalable, innovative method for improving the durability and reflectivity of polycarbonate-based mirrors, with significant implications for CSP applications. [ABSTRACT FROM AUTHOR]

Nickel electroplating is known to be industrially effective for enhancing various substrate properties. In the present work, nickel coatings were developed on copper substrates by electroplating using standard nickel plating solution at various electrolyte bath temperatures ranging from 40 ± 2°C to 60 ± 2°C in steps of 10°C. Energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were used to study the composition, phase structure and morphology of the coatings. The coatings were also analysed for hardness and porosity, and process current efficiency was measured. The electrolyte bath temperature has a profound effect on the nature of the developed nickel coatings, and is observed to have an impact on the surface morphology, crystallographic direction, and hardness, as well as deposition current efficiency. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of adding cerium oxide (CeO2) particles to the cutting fluid on the machining mechanism when slicing sapphire wafers using an electrodeposited diamond wire tool. The results showed that the added CeO2 acted to suppress wire tool deflection and promote initial wear of the nickel plating to rapidly expose the abrasive grains. In addition, elemental analysis of the shed wear particles suggested that they were adsorbed particles of nickel plating and sapphire. It was statistically confirmed that the CeO2 slurry reduced the size of the wear particles. In addition, the machining force was measured, and it was found that the CeO2 slurry reduced the machining force. Based on these results, it is the CeO2 slurry likely changed the wear mode from severe to mild and suppressed the lifting of the tool because smaller wear particle were formed. This suppressed wire tool deflection and stabilized the machining pressure to make the abrasive grains uniformly contact and remove material from the workpiece. Therefore, the number of cutting grains increased and the depth of cut per grain was kept small, which likely resulted in a transition to the crack-free ductile mode. [ABSTRACT FROM AUTHOR]

AbstractRoot lesion nematode of tea (Pratylenchus loosi) is one of the most dangerous and destructive pests in all areas of the world where tea grows. Rhizobacteria with nematicidal properties were screened using the soils of root lesion nematode-infected tea fields located in Guilan province, Iran. Effective bacteria were identified based on molecular and biochemical methods. Protease enzyme production was investigated on skim milk agar (1%) medium. The effects of temperature and pH on the amount of protease production by bacteria were investigated. Three protease inhibitors, namely PMSF, EDTA and 1,10-phenanthroline, were investigated. In total, 150 bacterial strains were isolated from tea rhizosphere using the spread-plating technique and nutrient agar medium, of which four bacterial isolates of Pseudomonas spp. had nematicidal properties in the range of 84.98% to 95.24%. Two of the bacterial isolates, RH25 (Pseudomonas aeruginosa) and RH37 (Pseudomonas fluorescens), had the largest clear zone of proteolysis on skim milk agar and were subjected to various biochemical tests. The influences of time (1 to 120 h), temperature (22 to 37°C) and pH (7.0 to 8.5) were investigated in the production of protease. The highest enzyme production was obtained from growing RH37 and RH25 on mineral medium when incubated at temperatures of 26°C and 30°C for 72 and 96 h and at initial pH values of 7.2 and 7.6, respectively. Proteases obtained from RH37 (P. fluorescens) belonged to the metalloprotease and serine protease families and the one produced by RH25 (P. aeruginosa) was a metalloprotease. According to the results of this research, the most effective control mechanism of these bacteria against nematodes is the production of bacterial protease. This mechanism can be exploited to control nematodes. [ABSTRACT FROM AUTHOR]

Adapting coating material for copper absorber tubes with fins probably plays a significant role, which should have higher absorptance and lower emissivity. This study used FPC heat transfer augmentation through an absorber tube integrated with black nickel blended with industrial black matt paint and the coating thickness at 0.3, 0.2, and 0.1 μm made via spray pyrolysis. Based on a thermal mathematical model, heat absorption, heat transfer coefficient, and thermal and exergy efficiency of FPC were estimated, and the results were compared with the non-coating FPC. The excellent coating thickness exhibits a peak absorptance (0.98) and emissivity (0.097), leading to improved heat transfer behaviour, specifically 0.1 μm thin film-coated FPC. Hence, the outlet temperature of the working fluid is approximately 96.1 °C, when utilizing a 0.1 μm thin film coating. It represents the highest outlet temperature observed among the coating conditions and non-coating absorber tubes. The exposure of 0.1 µm thin black nickel coated FPC recorded superior heat absorption and heat transfer coefficient values of 1689W and 140.58 W m−2 K−1. Similarly, the average thermal and exergy efficiency is about 74.3% and 54.9%, respectively, by 0.1 μm thin film coating absorber through higher absorptance and lower emissivity (0.097). Moreover, the 0.1 μm thin film coating exhibits the lowest entropy generation of about 0.00065 W K−1. It indicates that, in addition to achieving higher outlet temperatures, the 0.1 μm thin film coating performs more efficiently, minimizing irreversible processes. [ABSTRACT FROM AUTHOR]

Silicon interposers embedded with ultra-deep through-silicon vias (TSVs) are in great demand for the heterogeneous integration and packaging of opto-electronic chiplets and microelectromechanical systems (MEMS) devices. Considering the cost-effective and reliable manufacturing of ultra-deep TSVs, the formation of continuous barrier and seed layers remains a crucial challenge to solve. Herein, we present a novel dual catalysis-based electroless plating (ELP) technique by tailoring polyimide (PI) liner surfaces to fabricate dense combined Ni barrier/seed layers in ultra-deep TSVs. In additional to the conventional acid catalysis procedure, a prior catalytic step in an alkaline environment is proposed to hydrolyze the PI surface into a polyamide acid (PAA) interfacial layer, resulting in additional catalysts and the formation of a dense Ni layer that can function as both a barrier layer and a seed layer, particularly at the bottom of the deep TSV. TSVs with depths larger than 500 μm and no voids are successfully fabricated in this study. The fabrication process involves low costs and temperatures. For a fabricated 530-μm-deep TSV with a diameter of 70 μm, the measured depletion capacitance and leakage current are approximately 1.3 pF and 1.7 pA at 20 V, respectively, indicating good electrical properties. The proposed fabrication strategy can provide a cost-effective and feasible solution to the challenge of manufacturing ultra-deep TSVs for modern 3D heterogeneous integration and packaging applications. [ABSTRACT FROM AUTHOR]

A high purity Ni plating layer was obtained on the surface of the plain cotton fabric by electroless nickel plating. The micromorphology and elemental composition of the Ni plating layer were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Structural absorbing composites with glass fiber (GFs)/epoxy resin (EP) as permeable layer, nickel coated fabric/EP as absorbing layer and carbon fiber UD cloth (UDCFs)/EP as reflecting layer were prepared by vacuum assisted resin perfusion (VARI). The effects of different thicknesses on the microwave absorption properties and mechanical properties of composites were investigated. The results show that the lowest reflection loss (RL) is −31.02 dB, the effective absorbing bandwidth (RL < −10 dB) is 6.21 GHz (11.55 GHz - 17.76 GHz), and the maximum tensile and bending loads endured are 41.36 KN and 1.63 KN at 15.14 GHz with a thickness of 2.5 mm, which provides a good reference value for the subsequent preparation of magnetic/dielectric composites with both excellent microwave absorption and mechanical properties. [ABSTRACT FROM AUTHOR]

Anode‐free potassium (K) metal batteries are promising candidates in high‐energy‐density batteries. Nevertheless, the notorious potassium dendrite growth and poor K plating/stripping efficiency originating from the potassiophobicity of conventional Cu current collectors impede their practical applications. Herein, by means of systematically multi‐scale theoretical simulations, the correlations among K deposition morphology, nucleation sites, and potassiophilicity of mediation layers are well illuminated from thermodynamics and dynamics perspectives. As a proof of concept, a potassiophilic alloy Cu6Sn5 layer is constructed on commercial Cu foils via a facile electroless plating approach. The designed Cu6Sn5@Cu can guide the homogeneous distribution of K+ flux and regulate the electronic field, promoting uniform K+ plating and stripping. Meanwhile, a KF‐rich solid electrolyte interphase (SEI) layer with high mechanical strength is electrochemically induced and formed, facilitating the transport of K+ through SEI and enhancing the stability of SEI. Consequently, Cu6Sn5@Cu delivers great performance with durable stability of up to 600 h (1 mA cm−2 and 1 mAh cm−2) in no‐reservoir half‐cells. Benefiting from the unique mediation layer design, a novel anode‐free K‐metal full‐cell prototype demonstrates ameliorative cyclic stability. This work advances a fundamental understanding and establishes the bridge between the potassium deposition morphology and mediation layer properties for anode‐free potassium‐metal batteries. [ABSTRACT FROM AUTHOR]

The catalytic electroless plating on insulating substrate holds great potential in additive manufacturing of printing circuits. A tri-layer interpenetration architecture was constructed to improve the peeling strength of Cu plating layer. The corona-treated PET was coated by epoxy resin, which served as ground floor for the rooting of Cu NWs. Benefiting from high aspect ratio, the ends of Cu NWs were exposed to surface. Which assembled into middle layer, forming 3D Cu NWs catalytic arrays. Along with Cu electroless plating, the catalytic arrays were gradually filled up and covered by the top layer of Cu plating. Both epoxy resin layer and Cu plating layer were deeply rooted by Cu NWs, which afforded the Cu plating layer with 5B adhesion, an increase of 86% compared to that of Cu MSs catalyst. Through investigating the subsidence behavior of Cu NWs in epoxy resin adhesive layer, the strengthen mechanism of peeling strength of Cu plating layer has been validated. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to investigate the effect of chemical nickel plating and mechanical alloying on the mechanical and tribological properties of FeS/iron-based self-lubricating materials as well as the wear mechanism of the materials. Design/methodology/approach: Surface modification of FeS powder was carried out by chemical nickel plating method and mechanical alloying of mixed powder by ball milling. The mechanical properties of the material were tested by tribological testing by M-200 ring block type friction and wear tester. Optical microscope was used to observe the surface morphology of the material and the transfer film on the surface of the mate parts, and scanning electron microscope and EDS were used to characterize the wear surface. Findings: Mechanical alloying ball milling was carried out so that the lubricating particles in the matrix are uniformly dispersed; nickel-plated layer enhances the interfacial bonding of FeS and the matrix, and the combination of the two improves the mechanical properties of the material, and at the same time the friction side of the surface of the lubrication of FeS lubricant transfer film formed is denser and more intact, and the friction coefficient of friction side and the wear rate of the material have been greatly reduced. Originality/value: This work aims to improve the mechanical and tribological properties of FeS/iron-based self-lubricating materials and to provide a reference for the preparation of materials with excellent overall properties. [ABSTRACT FROM AUTHOR]

Electroplating is widely exploited in numerous application areas. Understanding the kinetics of electroplating, which is essentially a dynamic phenomenon, is crucial to making use of it appropriately in the real world. Currently, there exist a variety of research tools for studying electroplating kinetics, each with its own pros and cons. In this paper, we introduce a novel, immersion ultrasonic testing‐based technique that carries out in situ, direct monitoring of the thickness increase of an electroplated layer. Through careful design and optimization of the measurement setup and the signal processing protocol, the measurement resolution of the technique was able to reach a sub‐micron level. Via a number of demonstrative zinc plating experiments that were performed under different conditions, the measurement accuracy of the technique was thoroughly validated by a number of independent methods. All in all, the technique can become a promising alternative tool for studying the kinetics of different electroplating processes, supplementing the existing toolbox with the capability of providing a new class of information. [ABSTRACT FROM AUTHOR]

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study is to investigate how electroless nickel-phosphorus-coated Manganese Aluminum Bronze (MAB-CU4) alloys react to corrosion in a 0.5 M NaCl environment. Scanning electron microscopy examinations revealed that the coating layer has a cauliflower-like structure, and there are some porosities within the coating from the release of H2 gas during the coating's deposition. EDS analysis detected only Ni and P on the coating, while XRD analysis indicated that the coating has an amorphous and nanocrystalline structure. Electrochemical corrosion tests showed that the untreated MAB-Cu4 alloy's Ecorr value dropped to -0.47 V in 1000 seconds and then stabilized. Within 200 seconds, the Ni-P-coated MAB-Cu4 alloy's corrosion potential dropped to -0.425 V from -0.412 V. Then, a progressive increase brought the potential value to -0.395V around the 2000th second. Upon examination of the anodic polarisation curve for the Ni-P-coated MAB-Cu4 alloy, it was found that the Ecorr value was lower than that of the untreated alloy (-0.532 V). The Ni-P-coated sample exhibits higher intensity values at low and medium frequencies compared to the untreated sample, indicating that the corrosion mechanism is identical for both samples; however, the Ni-P-coated sample exhibits superior corrosion resistance. Considering the frequent exposure of MAB alloys to corrosive environments, the implementation of an electroless nickel phosphorus coating may potentially improve their resistance to corrosion and extend their operational lifespan. [ABSTRACT FROM AUTHOR]

This research aims to validate the capability of composite nickel-based membranes in separating hydrogen and to examine how multi-layer deposits influence the density of the nickel film. The study evaluated the hydrogen permselectivity of the membranes for both single gases (H 2 , N 2) and binary mixtures over a temperature range from 25 °C to 700 °C. The findings revealed that the thickness of the nickel layer (ranging from 2 μm to 37 μm) and its adhesion to the support material affected the hydrogen transport through the films. Increasing the number of electroless plating treatments and the nickel thickness on γ-alumina and α-alumina tubular supports resulted in decreased hydrogen permeance but improved hydrogen selectivity. This was attributed to the enhanced recovery of the γ-alumina support and efficient filling of α-alumina support pores, depending on the membrane type. The study identified multiple mechanisms contributing to hydrogen transport, including surface diffusion, Knudsen diffusion at lower temperatures (<300 °C), and activated diffusion processes at higher temperatures (>300 °C). At 700 °C, for a Ni/0.8 μm-α-Al 2 O 3 membrane with a 37 μm nickel film, the hydrogen permeance for single gases was 5.8 × 10−8 mol/m2 s Pa (189 GPU: gas permeance unit) with an ideal selectivity of 199 towards N 2. It was 7.3 × 10−8 mol/m2 s Pa (238 GPU) for gas mixtures with an H 2 /N 2 separation factor of 148. These results suggest that these membranes are particularly effective at high temperatures, emphasizing their potential for hydrogen separation applications and positioning them as promising materials for further development in this field. • Composite Membrane Success: Nickel-based membranes show remarkable efficiency in hydrogen separation. • Optimized Thickness: Balancing nickel layer thickness enhances hydrogen permeance and selectivity. • Temperature-Dependent Mechanisms: The study reveals diverse hydrogen transport modes at different temperatures. • Nickel's Thermal Resilience: High-temperature performance without hydrogen embrittlement highlights nickel's potential. • Application Versatility: Membranes demonstrate effectiveness for both single gases and binary mixtures. [ABSTRACT FROM AUTHOR]

Electroless nickel plating is a suitable technology for the hydrogen industry because electroless nickel can be mass-produced at a low cost. Investigating in a complex environment where hydrogen permeation and friction/wear work simultaneously is necessary to apply it to hydrogen valves for hydrogen fuel cell vehicles. In this research, the effects of hydrogen permeation on the mechanical characteristics of electroless nickel-plated free-cutting steel (SUM 24L) were investigated. Due to the inherent characteristics of electroless nickel plating, the damage (cracks and delamination of grain) and micro-particles by hydrogen permeation were clearly observed at the grain boundaries and triple junctions. In particular, the cracks grew from grain boundary toward the intergranualr. This is because the grain boundaries and triple junctions are hydrogen permeation pathways and increasing area of the hydrogen partial pressure. As a result, its surface roughness increased by a maximum of two times, and its hardness and adhesion strength decreased by hydrogen permeation. In particular, hydrogen permeation increased the friction coefficient of the electroless nickel-plated layer, and the damage caused by adhesive wear was significantly greater, increasing the wear depth by up to 5.7 times. This is believed to be due to the decreasing in wear resistance of the electroless nickel plating layer damaged by hydrogen permeation. Nevertheless, the Vickers hardness and the friction coefficient of the electroless nickel plating layer were improved by about 3 and 5.6 times, respectively, compared with those of the free-cutting steel. In particular, the electroless nickel-plated specimens with hydrogen embrittlement exhibited significantly better mechanical characteristics and wear resistance than the free-cutting steel. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of Ni(II) ions at a glassy carbon electrode was studied using choline chloride–ethylene glycol (ChCl-EG) and ethylene glycol (EG) as solvents. The deposition behavior of Ni(II) was investigated by cyclic voltammetry (CV) tests. The results showed that the reduction of Ni(II) in both non-aqueous solvents was an irreversible process controlled by diffusion, and that the cathodic efficiency and the diffusion coefficient of Ni(II) in EG were higher. The nucleation process of Ni was investigated in detail by chronoamperometry (CA) experiments, and the results showed that the reactions of Ni in EG and ChCl-EG conformed to the three-dimensional transient nucleation mechanism and continuous nucleation mechanism. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) were used to study the microscopic morphology and phase composition of the \nickel plating, and it was verified that different species of complex anions [NiCl3(EG)3]− and [NiCl4]2− affected the morphology and density of \nickel metal, and that the nickel plating in EG had small "needle-like" nuclei. The corrosion resistance of the nickel plating was investigated by polarization curves and AC impedance tests, and the results showed that the nickel plating obtained by electrodeposition in EG and EG-NaCl had the best corrosion resistance. [ABSTRACT FROM AUTHOR]

Magnetostriction-based electromagnetic acoustic transducer (M-EMAT) is a promising tool for generating fundamental shear-horizontal (SH0) mode guided waves in plate. Though the M-EMAT possesses high-order harmonics excitation ability in nature, its conventional way can only generate a fundamental component of SH0 mode. The analytical modeling was performed in this study to releasing the ability of M-EMAT in generating odd harmonics of SH0 mode. First, the inaccurate conditions of magnetic fields for relative permeability calculation in the existing model are corrected in the proposed model. Second, the error of the existing model in predicting the spectrum of the SH0 mode generated in Nickel plate is estimated. Third, numerical solutions are provided by the improved model to examine the key factors governing the ability of M-EMAT in generating odd harmonics of SH0 mode. The conclusions demonstrated that the intensity ratio (HS/HD) of static and dynamic magnetic fields is adjusted below 1 and the ability of M-EMAT in generating odd harmonics of SH0 mode can be activated. The normalized amplitude of 3rd harmonics decays exponentially with the increase of HS/HD, which is independent of geometrical parameters of M-EMAT. The improved model can effectively optimize excitation parameters of M-EMAT and generate odd harmonics of SH0 mode in plate. [ABSTRACT FROM AUTHOR]

Electroplating nickel-63, a radioactive isotope used in betavoltaic batteries and random number generators, requires precise control due to its limited availability and the generation of radioactive waste. To minimize waste and ensure effective plating, small plating baths are employed, optimizing the process within constrained conditions. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were utilized to determine the optimal plating conditions and limiting conditions for nickel electroplating in a small plating bath. This study focuses on the use of low-concentration nickel solutions and small plating equipment, in contrast to the common industrial practice of using high concentrations of nickel. Here, it is important to optimize the plating parameters, especially the nickel concentration, current density, and bath temperature. An average thickness of 1.8 μm was found when plating with a nickel concentration of 0.06 M, a current density of 5 mA/cm2, and a solution temperature of 40 °C, while ideal conditions were found to achieve the theoretical maximum energy and 90% release rate when plating with nickel-63 instead of Ni. [ABSTRACT FROM AUTHOR]

The drilling and sampling technique is the preferred method for lunar soil sample collection. In response to the poor wettability of the AgCuNiMn brazing alloy that is utilized for the lunar soil drilling tools on the surface of Inconel 718 superalloy, a nickel plating process was adopted for surface modification of the superalloys. Under the conditions of 890 °C and 10 min, the influence of nickel plating and different plating thicknesses on the wettability and gap-filling capability of the brazing alloy, as well as the microstructure and mechanical characteristics of the joints, were investigated. An analysis was done on the brazed joints' microstructural development process and strengthening mechanism. The findings show that nickel plating on the superalloys' surfaces considerably increases the brazing alloy's wettability to the substrate and its gap-filling capacity. The gaps between the base materials are closed, and the contact angle between the brazing alloy and the superalloy surface is decreased from 20 to 4°. With an increase in plating thickness, the joint's shear strength initially rises and subsequently falls. When the plating thickness is 28 μm, the shear strength is increased by 43.5% (from 168 to 241 MPa) compared to the unplated brazed joint. [ABSTRACT FROM AUTHOR]

Electroless nickel plating is widely used to improve the functional characteristics of the engineering parts produced by different manufacturing processes. In most of the cases, these plated surfaces require precision finishing to achieve the desired optical properties for mirror applications. It is difficult to get a high level of surface finish using conventional finishing techniques because of high forces and heat generation. It may result in degradation in the surface properties. In the present work, a compliant finishing tool is used to achieve a surface roughness at the nanoscale on the nickel-plated surface with stainless steel as substrate. The residual stress influences the optical properties of the finished surface. The x-ray diffraction is used to analyze the phase and residual stress on the substrate, as-plated, and ultra-precision finished surface. Microhardness and wear characteristics of these samples are also studied to understand the effect of surface finishing operation on nickel plating. The hardness of the as-plated surface is much higher than the substrate, and there is negligible effect of finishing process on the hardness. Both as-plated and finished surfaces show better wear resistance. [ABSTRACT FROM AUTHOR]

The development of Li-ion battery cases requires superior electrical conductivity, strength, and corrosion resistance for both cathode and anode to enhance safety and performance. Among the various battery case materials, super duplex stainless steel (SDSS), which is composed of austenite and ferrite as two-phase stainless steel, exhibits outstanding strength and corrosion resistance. However, stainless steel, which is an iron-based material, tends to have lower electrical conductivity. Nevertheless, nickel-plating SDSS can achieve excellent electrical conductivity, making it suitable for Li-ion battery cases. Therefore, this study analysed the plating behaviour of SDSS plates after nickel plating to leverage their exceptional strength and corrosion resistance. Electroless Ni plating was performed to analyse the plating behaviour, and the plating behaviour was studied with reference to different plating durations. Heat treatment was conducted at 1000 °C for one hour, followed by cooling at 50 °C/s. Post-heat treatment, the analysis of phases was executed using FE-SEM, EDS, and EPMA. Electroless Ni plating was performed at 60–300 s. The plating duration after the heat treatment was up to 300 s, and the behaviour of the materials was observed using FE-SEM. The phase analysis concerning different plating durations was conducted using XRD. Post-heat treatment, the precipitated secondary phases in SAF2507 were identified as Sigma, Chi, and CrN, approximating a 13% distribution. During the electroless Ni plating, the secondary phase exhibited a plating rate equivalent to that of ferrite, entirely plating at around 180 s. Further increments in plating time displayed growth of the plating layer from the austenite direction towards the ferrite, accompanied by a reduced influence from the substrate. Despite the differences in composition, both the secondary phase and austenite demonstrated comparable plating rates, showing that electroless Ni plating on SDSS was primarily influenced by the substrate, a finding which was primarily confirmed through phase analysis. [ABSTRACT FROM AUTHOR]

This study reports novel, compact, and additively manufactured quadrupole mass filters (QMFs) with adequate filtering performance for practical mass spectrometry applications. The QMFs are monolithically fabricated via vat photopolymerization of glass‐ceramic resin using 57 µm × 57 µm × 100 µm voxels, and selective electroless plating of nickel‐boron. Experimental characterization of QMF prototypes at 1.74 MHz using FC‐43 yields 131 Da peaks with 0.50 Da full width at half maximum (260 resolution), surpassing the resolution of reported miniaturized counterparts under similar conditions, and being on par with commercial, non‐miniaturized, heavier devices. The sensitivity of the 3D‐printed devices is estimated at 0.13 mA Torr−1 (comparable to that of optimized, commercial counterparts), while the devices attained up to 250 Da of mass range (limited by the driving electronics). The work is of interest to low‐cost, capable mass spectrometry, 3D‐printed instruments, and in‐space manufacturing of complex instrumentation. [ABSTRACT FROM AUTHOR]

Among the various reinforcement phases available in Cu-based composites, the unique layered structure and easy diffusion of A-layer atoms make MAX phases more suitable for reinforcing a copper matrix than others. In this study, Cu-coated Ti3AlC2 particles (Cu@Ti3AlC2) were prepared through electroless plating, and Cu@Ti3AlC2/Cu composites were fabricated via vacuum hot-press sintering. The phase composition and microstructure of both Cu@Ti3AlC2 powder and composites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results demonstrate the creation of successful electroless copper plating to obtain a Cu coating on Ti3AlC2 particles. At 850 °C, a small amount of Ti3AlC2 particles decompose to form TiCx, while Al atoms from the A layer of MAX phase diffuse into the Cu matrix to form a solid solution with Cu(Al). The test results reveal that the density of the Cu@Ti3AlC2/Cu composite reaches 98.5%, with a maximum compressive strength of 705 MPa, which is 8.29% higher than that of the Ti3AlC2/Cu composite. Additionally, the compressive strain reaches 37.6%, representing an increase of 12.24% compared to that exhibited by the Ti3AlC2/Cu composite. [ABSTRACT FROM AUTHOR]

With increasing demand for Li-ion batteries, studies are focusing on enhancing battery performance and safety. However, studies on battery cases remain scarce. Herein, we propose the use of super duplex stainless steel SAF2507, which is a two-phase (austenite + ferrite) steel, for battery casings. Unlike conventional AISI304, SAF2507 maintains its corrosion resistance and strength at high temperatures and precipitates a secondary phase at approximately 975 °C. However, the effects of Ni plating on this secondary phase are not well documented. Therefore, the electroless Ni plating of SAF2507 after secondary-phase precipitation was studied. Briefly, heat treatment at 1000 °C was used to induce precipitation, and the electroless Ni plating behaviour over varying plating periods was analysed using open-circuit potential, potentiodynamic polarisation, and electrochemical impedance spectroscopy measurements. The plating state and corrosion behaviour were examined using scanning electron microscopy. Heat-treated SAF2507 steel with a secondary phase exhibited excellent electroless Ni plating behaviour, which enhances the safety and durability of Li-ion batteries. Furthermore, uniform plating and electrochemical behaviour were achieved after 180 s, suggesting that SAF2507 is superior to AISI304. These findings contribute to the development of safer and more efficient batteries and address the growing demand for Li-ion battery case materials. [ABSTRACT FROM AUTHOR]

This work was undertaken to study the electrodeposition of tungsten from the Na2WO4-B2O3 system in the molten state. The measurement of the EMF being made with platinum-oxygen indicator and tungsten relative electrodes versus platinum-oxygen. Experiment due to dependencies of the platinum-oxygen potential and tungsten electrodes on the B2O3 concentration, are validate by the forming of ditungstate ions W2O72- in the high temperature ionic liquids (HTILs). The electroreduction process of the active species, is controlled by the diffusion; the rate of formation of the active species does not limit the electrode process; Polarization, in galvanostatic and potentiodynamic mode, have highlighted the fact that charge transfer is reversible. In the Na2WO4-B2O3 melt (acid-basic character), in a narrow potential range and at a controlled process potential, the electroreduction of tungsten from its dimeric form is possible due to the multielectronic processes that take place at the electrode surface. This study played an important role in the evolution tungsten coatings; the corrosion potentials of electrodes (copper, nickel, steel) plated with tungsten, were also measured. In this study, the influence of some parameters (temperature, electrolysis time, cathodic current density, B2O3 concentration) on the cathodic structure and composition was quantified, determining the optimal conditions of the reverse electrodeposition. [ABSTRACT FROM AUTHOR]

In this paper, electroless nickel plating is explored for the protection of binder-jetting-based additively manufactured (AM) composite materials. Electroless nickel plating was attempted on binder-jetted composites composed of stainless steel and bronze, resulting in differences in the physicochemical properties. We investigated the impact of surface finishing, plating solution chemistry, and plating parameters to attain a wide range of surface morphologies and roughness levels. We employed the Keyence microscope to quantitatively evaluate dramatically different surface properties before and after the coating of AM composites. Scanning electron microscopy revealed a wide range of microstructural properties in relation to each combination of surface finishing and coating parameters. We studied chempolishing, plasma cleaning, and organic cleaning as the surface preparation methods prior to coating. We found that surface preparation dictated the surface roughness. Taguchi statistical analysis was performed to investigate the relative strength of experimental factors and interconnectedness among process parameters to attain optimum coating qualities. The quantitative impacts of phosphorous level, temperature, surface preparation, and time factor on the roughness of the nickel-plated surface were 17.95%, 8.2%, 50.02%, and 13.21%, respectively. On the other hand, the quantitative impacts of phosphorous level, temperature, surface preparation, and time factor on the thickness of nickel plating were 35.12%, 41.40%, 3.87%, and 18.24%, respectively. The optimum combination of the factors' level projected the lowest roughness of Ra at 7.76 µm. The optimum combination of the factors' level projected the maximum achievable thickness of ~149 µm. This paper provides insights into coating process for overcoming the sensitivity of AM composites in hazardous application spaces via robust coating. [ABSTRACT FROM AUTHOR]

This study delves into the drag-reducing properties of nickel plating coatings applied to hydraulic pipelines. To investigate the drag reduction characteristics of pipeline coatings, we designed a specialized experimental apparatus to conduct deceleration experiments. The primary objective was to systematically assess the drag reduction effect of varying coating thicknesses on liquid flow within the pipeline. Chemical nickel plating was employed for preparing drag reduction coatings with diverse thicknesses, achieved through precise adjustments in the composition and operating conditions of the plating solution. In the design of the experimental apparatus, careful consideration was given to crucial parameters such as the inner diameter of the pipeline, the inlet flow rate, and the control of experimental variables. It quantitatively assesses how varying coating thicknesses, flow velocities, and pipeline diameters impact the pipelines' resistance to flow. By meticulously measuring the pressure differential across the pipeline, the research evaluates the extent of drag reduction afforded by the coatings and simultaneously elucidates the underlying mechanisms. Findings indicate a peak drag reduction rate of 5% under conditions of a 20 µm-thick nickel coating, 5 m/s flow velocity, and a 10 mm pipeline diameter. This study aims to comprehend how coatings affect linear losses along the pipeline, thereby establishing the groundwork for optimizing drag reduction technology. These outcomes highlight the coatings' potential to mitigate linear losses due to shear stress during fluid transport, offering a viable solution to enhance hydraulic pipeline efficiency with significant industrial implications. [ABSTRACT FROM AUTHOR]

The growing prominence of the electric vehicle industry, fueled by environmental concerns, has demanded innovation in various aspects of battery technologies with special emphasis on increasing the efficiency of both electric storage and its retrieval. An unexplored area of this is to identify the possibilities and limits of laser soldering. Here, we reveal the effects of surface pretreatment conditions and the amount of filler, along with the laser power and irradiation time on the characteristics of laser-soldered joints, by simultaneously evaluating the electrical and mechanical behavior of laser-soldered nickel-plated steel sheets (Hilumin®). By describing the morphological characteristics of the resolidified solder and the electrical and mechanical properties of the joints, we identify three, characteristically different morphological appearances and highlight the optimal one, where uniform and mostly void-free solder can be produced. Furthermore, we report a correlation between the threshold of upper sheet melting (either expressed as laser power or irradiation time) and joint deterioration in terms of the electrical and mechanical properties of the joint. We conclude that laser soldering can create joints with outstanding electrical conductance and adequate mechanical stability that meets the critical specifications of battery joining technologies when the surface pretreatment condition and processing parameters are properly optimized. [ABSTRACT FROM AUTHOR]

Silicon nitride (Si3N4) particle-reinforced aluminum–copper (Al-Cu) alloy matrix composites have been prepared in our previous works and experimental result shows that they can be used as a new kind of water-lubricated materials. However, the wettability between Si3N4 ceramics and Al-Cu alloys is poor and the manufacturing process is usually carried out at a high temperature of 1100 °C. To overcome this shortcoming, a layer of nickel was deposited on the surface of Si3N4 particles, forming a core-shell structure. Thus, the interface bonding property between Si3N4 and Al-Cu alloy can be improved and the lower sintering temperature can be applied. Si3N4/Al-Cu alloy composites with different proportions of Ni-coated Si3N4 were fabricated by powder matrix metallurgy technology at 800 °C, and the water lubrication properties of the composite were investigated. The experimental results show that with the increase in the particle content (10 wt%–40 wt%), the microhardness of the composites increased first and then decreased, while the porosity increased continuously. A low friction coefficient (0.001–0.005) can be achieved for the composites with the lower particle content (10 wt%–20 wt%). The major wear mechanism changes from the mechanically dominated wear during the running-in process to the tribochemical wear at the low frictional stage. [ABSTRACT FROM AUTHOR]

The emergence of defects during the early production phases of ferrous-alloy additively manufactured (AM) parts poses a serious threat to their versatility and adversely impacts their overall mechanical performance in industries ranging from aerospace engineering to medicine. Lack of fusion and gas entrapment during the manufacturing stages leads to increased surface roughness and porosities in the finished part. In this study, the efficacy of employing electroless nickel–boron (Ni-B) deposition to fill and level simulated AM defects was evaluated. The approach to levelling was inspired by the electrochemical deposition techniques used to fill vias in the electronics industry that (to some extent) resemble the size and shape of AM-type defects. This work investigated the use of surfactants to attenuate surface roughness in electroless nickel coatings, thereby achieving the preferential inhibition of the coating thickness on the surface and promoting the filling of the simulated defects. A cationic surfactant molecule, CTAB (cetyltrimethyl ammonium bromide), and a nonpolar surfactant, PEG (polyethylene glycol), at different concentrations were tested using a Ni-B electrolyte for the levelling study. It was found that the use of electroless Ni-B to fill simulated defects on ferrous alloys was strongly influenced by the concentration and nature of the surfactant. The highest levelling percentages were obtained for the heavy-molecular-weight PEG-mediated coatings at 1.2 g/L. The results suggest that electroless Ni-B deposition could be a novel and facile approach to filling defects in ferrous-based AM parts. [ABSTRACT FROM AUTHOR]