Nickel Plating Research Articles

Flexible and lightweight metalized polyamide nonwoven for electromagnetic interference shielding, electrothermal, photothermal, and antibacterial applications

The adoption of multifunctional nonwovens (NWs), which have more than one primary use, is increasing worldwide. In this paper, metalized nylon 6 NWs are prepared using nickel–phosphor (Ni-P) plating for electromagnetic shielding, electrothermal, photothermal, and antibacterial applications. The sensitized and activated NWs are deposited in an electroless nickel plating for different durations. The deposition amount increased in the electroless plating process from 1 to 8 min. Afterward, the precipitation rate of Ni-P particles decreases, and the coated surface of the NWs also becomes non-uniform. Surface morphology and elemental analysis mapping showed that Ni-P particles are uniformly deposited on surfaces of Ni-P/NWs with 8 min electroless plating. As a result, it is shown that the sample with 8 min electroless plating is the optimal and best sample to use in the shielding effectiveness of 55.4 dB, and specific shielding of 490.27 dB.cm3.g−1. Also, the optimal specimen has the best electrothermal application with an average maximum temperature of 133.5 °C at 5 V with relative preservation of the necessary properties of the fabric, compared to other prepared samples. Also, this optimal fabric in the photothermal performance, reaches an average maximum temperature of 77.9 °C in 800 mW/cm2. The optimal sample shows significant antibacterial efficiency against E. coli and S. aureus bacteria and reaches 62.70 ± 0.20 and 88.30 ± 1.30 % under light irradiation, respectively. The results show that the optimal sample with great washing durability can perform very well in cold environments and exhibit excellent shielding, electrothermal, and photothermal performances which can be used as lightweight electro-heating and shielding fabrics.

Control system and process optimization for electroless nickel plating

A novel method based on mid-frequency vibration is proposed to eliminate coating defects such as bubbles during electroless nickel plating. An automated control system for the plating, enabling precise and stable measurements and adjustments of critical parameters such as plating solution temperature, pH, and nickel ion concentration, is also established, which significantly improves process efficiency and coating quality. Experimental results indicate that the system is capable of realizing stable operation over extended periods. A nonporous nickel–phosphorus coating with a thickness greater than 200 μm is successfully obtained, with high phosphorus content, robust adhesion, and superior machinability.

Investigations of the Interface Design of Polyetheretherketone Filament Yarn Considering Plasma Torch Treatment

Taking advantage of its high-temperature resistance and elongation properties, conductive-coated polyetheretherketone (PEEK) filament yarn can be used as a textile-based electroconductive functional element, in particular as a strain sensor. This study describes the development of electrical conductivity on an inert PEEK filament surface by the deposition of metallic nickel (Ni) layers via an electroless galvanic plating process. To enhance the adhesion properties of the nickel layer, both PEEK multifilament and monofilament yarn surfaces were metalized by plasma torch pretreatment, followed by nickel plating. Electrical characterizations indicate the potential of nickel-coated PEEK for structural monitoring in textile-reinforced composites. In addition, surface energy measurements before and after plasma torch pretreatment, surface morphology, nickel layer thickness, chemical structure changes, and mechanical properties were analyzed and compared with untreated PEEK. The thickness of the Ni layer was measured and showed an average thickness of 1.25 µm for the multifilament yarn and 3.36 µm for the monofilament yarn. FTIR analysis confirmed the presence of new functional groups on the PEEK surface after plasma torch pretreatment, indicating a successful modification of the surface chemistry. Mechanical testing showed an increase in tensile strength after plasma torch pretreatment but a decrease after nickel plating. In conclusion, this study successfully developed conductive PEEK yarns through plasma torch pretreatment and nickel plating.

Surface characterization of the diamond polishing pads and their performance evaluation in nanofinishing of electroless nickel plating

Surface characterization of the diamond polishing pads and their performance evaluation in nanofinishing of electroless nickel plating

Stretchable liquid metal grid/metallized polyurethane composites with switchable electromagnetic interference shielding and efficient infrared stealth performance

Intelligent electromagnetic interference (EMI) shielding materials with tunable electromagnetic shielding properties becomes a significant and urgent concern for information society. Hence, a switchable and low-reflectivity EMI shielding composite is fabricated by electroless nickel plating on the surface of polyurethane nonwoven fabric (Ni@TPU), and followed by combining with liquid metal (LM) grid. The synergistic combination of Ni@TPU and LM grid effectively facilitates the rational construction of hierarchical impedance matching. Meanwhile, it promotes destructive interference between electromagnetic waves reflected from Ni@TPU and the LM grid. As a result, an excellent low-reflectivity EMI shielding performance can be achieved. More importantly, the switchable EMI shielding performance can be easily realized by repeatedly stretching Ni@TPU/LM. In addition, the fluffy nonwoven fabric and LM grid with low infrared emissivity endow it with an outstanding infrared stealth performance. Such excellent low-reflectivity EMI shielding switch performance incorporated with flexible infrared stealth makes it possible to become smart EMI shielding material with a great promise to be employed in the application scenario of window in camouflage container.

Interfacial metallization in segregated structured PEEK composite for enhanced thermal conductivity and electromagnetic interference shielding

The increasing integration of electronic devices has created an urgent demand for multi-functional composites with efficient thermal management and electromagnetic interference (EMI) shielding. In this study, a three-dimensional (3D) continuous metal–carbon hybrid thermally/electrically conductive network structure is fabricated by in-situ nickel plating of core–shell structured polyetheretherketone (PEEK) hybrid particles. The hybrid particles realize phonon and electron dual heat-transfer pathways and reduce the interfacial thermal resistance by using metallic Ni nanoparticles to bridge the gap. Furthermore, the interfacial metallization and segregated structure significantly enrich the multiple electromagnetic wave reflection and attenuation mechanisms. The PEEK composites with metallized-segregated structure and filler content of 28.26 vol% exhibit an excellent through-plane thermal conductivity of 6.52 W m−1·K−1 and an efficient EMI shielding of 91 dB, thus demonstrating their significant potential as multi-functional thermal management materials. The heat-transfer and EMI shielding process of the composites can be visualised using the finite element model, which further proves the effectiveness of the segregated structure and metallization. This simple and efficient strategy is expected to facilitate the manufacture of multi-functional thermal management composites with high thermal conductivity and excellent EMI shielding.

Preparation mechanism and characterization of PET/Cu composite foils

PET/Cu composite foils are expected to have widespread applications due to their lightweight, good bendability and excellent electrical conductivity. However, efficiently and stably preparing copper cladding layers on the surface of PET film with good bonding to the substrate remains a challenge. In this study, by optimizing the process route and adopting a synergistic method involving electroless plating and electroplating, PET/Cu composite foils with excellent conductivity and robust bonding can be successfully prepared. The experimental results indicate that the optimal performance of PET/Cu composite foils is achieved when the PET substrate is roughened with KMnO4/H+ solution, activated with salt-based colloidal palladium, subsequently treated with a weak alkaline electroless nickel plating solution for 5 min, and plated copper at a current density of 0.4 A·dm−2. The adhesion strength of the PET/Cu composite foils meets the ASTM 5B standard and the electrical conductivity reaches up to 4.17 × 107 S/m. The method proposed in this study offers an efficient and concise approach for preparing high-quality PET/Cu composite foils that hold great potential for diverse applications in flexible copper clad laminates.

Comparative study of Ni nanoparticles synthetized using electroless Ni plating waste and an analytical Ni reagent. Characterization and possible application in magnetic fluids

Wastewater from the electroless industry represents a potential danger to the environment and health, mainly due to its heavy metal content. In this study, nickel nanoparticles were synthesized through chemical reduction precipitation by using an electroless nickel plating waste and hydrazine sulfate as reducing agent. The aim of the present work is twofold. First we want to extract the metal from the aqueous medium, minimizing its content to levels allowed by environmental regulations. Second, we aim to valorize the residue by recovering the precipitated nickel to be applied as a solid phase in a magnetic fluid (MF). It is found that the present synthesis method using N2H4 as reducing agent, allowed us to minimize the Ni concentration in the aqueous waste in 97.49 %. The properties of the recovered Ni precipitate is compared with the Ni nanoparticles (NPs) obtained from a solution prepared with analytical grade nickel sulfate. The synthesized materials from both the waste (Ni-R) and analytical reagent (Ni-A) were characterized by comparing their chemical, physical, and morphological properties. In both cases, the Ni-R and Ni-A precipitates, spherical Ni NPs of 8–10 nm crystallite sizes are obtained, agglomerated in a bimodal size distribution centered at 174.6 and 383.4 nm, and a monomodal size distribution centered at 63.6 nm, respectively. Both Ni precipitated samples are ferromagnetic, but the Ni-R sample has a higher magnetic saturation of 40 emu/g compared to 8 emu/g of the Ni-A sample. The difference in the rheological behavior of both precipitates could be attributed to the presence of surface oxidation having a relatively less contribution in the case of the Ni-R particles due to the higher average size of the particles. The Fe content, probably coming from the nickel-plated parts in spent baths, is slightly higher in the Ni-R sample. Thus, the present work shows that it is possible to valorize an industrial Ni-based residue, by obtaining Ni precipitates that in magnetic fluids give even better results than those expected under more rigorous experimental conditions, i.e., in cases where the quality of the chemical precursors is usually a determining factor.

PTFE layer formation during brush electroplating of nickel

Brush electrodeposition of Ni/PTFE composite coatings was explored using a nickel high speed solution and polytetrafluoroethylene (PTFE) particles 6–9 μm in diameter. A novel bilayer-like, partially intercalated structure was produced, consisting of a rough nickel sublayer covered by an outer, compact, smooth PTFE layer. The study of the coating growth revealed that the PTFE particles bind together on the nickel coating valleys and grow until all the surface is covered by a polymer layer without the need of a baking stage. The resulting coating presents a hydrophobic surface with a low coefficient of friction (0.10) and higher corrosion resistance to salt spray testing than the nodular nickel coating. The coatings were produced using an aqueous nickel plating solution, where the hydrophobic PTFE particles were suspended using different substances: cetrimonium bromide (CTAB) cationic surfactant, isopropyl alcohol premixed with the particles, and ethanol premixed with the particles. High concentrations of the suspending products were detrimental for the deposition process, but optimal values of 0.1 g/l, 3 ml/l and 3 ml/l respectively were found. All compounds successfully suspended the PTFE particles and both alcohols produced the Ni/PTFE coating described before, but the CTAB failed to co-deposit the polymer.

Synthesis and properties of multi-porous multi-doped nano-Na3V2(PO4)3@C materials from electroless nickel plating wastewater

Synthesis and properties of multi-porous multi-doped nano-Na3V2(PO4)3@C materials from electroless nickel plating wastewater

Gluconate solutions for nickel electrodeposition and nickel electroless plating

Nickel electroplating has found a wide range of industrial applications as a technique for creating protective and decorative coatings of metallic and non-metallic surfaces, protecting materials against corrosion at elevated temperatures in both alkaline environments and organic acid solutions, forming a sublayer for obtaining coatings of other metals on steel, enhancing the hardness and wear resistance of surfaces, as well as for improving solderability. Such coatings can be obtained from weakly acidic aqueous and weakly alkaline complex electrolytes. In this review, we analyze the available literature on complexation of nickel(+2) with D-gluconate ion CH2OH(CHOH)4COO‾, along with that on compositions and some technological characteristics of complex D-gluconate solutions for nickel electrodeposition and electroless plating. Thus, a corrosion-resistant smooth light-colored nickel coating, tightly adhered to a copper substrate, was obtained from an electrolyte with a pH level of 8, containing 53 g/dm3 of NiSO4 •6H2O, 44 g/dm3 of D-C6H11O7Na, 25 g/dm3 of H3BO3, 53 g/dm3 of (NH4)2SO4, and 0.5–3 g/dm3 of CO(NH2)2, at a temperature of 25 °C, a cathodic current density of 2.5 A/dm2 with a current efficiency of 96.4%. An electroless Ni-P(3–18 wt%) alloy coating on copper was obtained from a solution with a pH level of 9, containing 5–30 g/dm3 of NiSO4 •6H2O, 10–60 g/dm3 of D-C6H11O7Na, 5–40 g/dm3 of NaH2PO2 •H2O, 3 g/dm3 of HOOCCH2CH2COOH, 0.5 g/dm3 of CH3(CH2)11OSO3Na, 0.002 g/dm3 of Pb(CH3COO)2•3H2O, at a temperature of 90 °C and a deposition rate of up to 0.75 μm/min. The review also discusses methods for preparing D-gluconate electrolytes for nickel plating using sodium D-gluconate, D-glucono-1,5-lactone, and nickel D-gluconate. One advantage of D-gluconate nickel plating solutions consists in the absence of toxicity and low cost of D-gluconates.

STRUCTURE FORMATION OF Ni−P ALLOY ELECTROCOATINGS WITH INCREASED CORROSION RESISTANCE

Purpose of research. The main factors that reduce the protective properties of electrocrystallized coatings are the formation of volumetric defects − pores, as well as the occurrence of microgalvanic couples at grain boundaries, that is, on surface defects of the crystalline structure. Creating a non-porous structure in electrocoatings, eliminating the formation of surface defects in metal/alloy layers, as well as the possibility of replacing chromium coatings, which are obtained from toxic electrolytes, are urgent tasks. Materials and methodology. In the work, it was proposed to use electrocoatings with Ni−P alloy as protective layers on products that increase corrosion resistance. An X-ray determination of the phase composition of Ni−P electrochemical deposits was carried out. The surface morphology and corrosion resistance of coatings were studied. Results. Samples of electrochemical coatings of pure nickel and nickel-phosphorus alloy were studied. It has been established that during the formation of nickel coatings with the addition of phosphorus ions, the surface morphology has practically no pores, amorphization of deposits occurs, due to which the protective properties, namely, corrosion resistance, are improved. Scientific novelty. Factors have been identified that influence the increase in corrosion resistance of coatings − the absence of a porous structure and the formation of an amorphous state. Conclusions. The influence on the structure and properties of electrochemical coatings of a nickel-phosphorus alloy has been studied. It has been established that the addition of phosphorus ions to the nickel plating electrolyte leads to the formation of an amorphous structure in the coatings, and layers of the Ni−P alloy appear practically without the presence of pores. It has been established that the effect of increasing the corrosion resistance of the electrochemical coating with a nickel-phosphorus alloy (by 30 %) is due to the formation of an amorphous structure of the solidifying metal liquid while preventing the crystallization process during electrochemical deposition.

A New Process for Efficient Non-Destructive Metal-Activated Composite Plating of Ni-P-Al2O3 on Titanium Base and Its Performance Research

A new high efficient and non-destructive mental activation process of electroless composite plating was proposed. The process utilized electromagnetic induction equipment to heat the titanium alloy substrate and used its energy to complete the activation process, which could successfully attach the nickel nanoparticles firmly to the surface of the titanium alloy; at the same time, the process pre-activated Al2O3 nanoparticles and added the activated nanoparticles to the plating solution. In the process of plating, the activated titanium substrate was used as the catalytic center of electroless nickel plating (ENP) for electroless composite plating. The new activation process avoided complicated traditional processes such as acid etching and zinc dipping. Such traditional processes require huge doses of chemicals, including various strong acids, so improper waste liquid treatment will cause harm to the environment. The important parameters of the process were optimized by orthogonal experiments. A scanning electron microscope (SEM), an X-ray photoelectron spectroscopy (XPS), an energy dispersive spectrometer (EDS), thermal shock experiments and friction and wear experiments were used to characterize and analyze the surface morphology, composition, binding force and friction coefficient of the coating, and analyze the coating quality by measuring the plating rate and the thickness of the coating. The results showed that the rate of electroless composite plating increased with the increase in Al2O3 nanoparticle concentration. When the concentration of Al2O3 nanoparticles reached 1.5 g/L, the ENP rate decreased with the increase in Al2O3 nanoparticle concentration. The adhesion of the sample was evaluated by the scratch test, which showed that the binding grade of the sample was 0, and the Vickers hardness was 688.5 HV. Results showed that the coating produced by this new process has excellent performance. Therefore, the process is an environmentally friendly and fast activation composite plating process.

Research on the Mechanism of Oxygen-Induced Embrittlement Fracturing in Industrial Electrolytic Nickel.

In this study, severe cracking occurred during an investigation of the direct hot rolling of industrial electrolytic nickel plates. To determine the cause of hot-rolling cracking, the microstructure phase composition was analyzed through the utilization of various techniques, including optical microscopy, scanning electron microscopy, electron backscattering diffraction, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and electron probe micro-analysis. The comparative microstructural analysis took place between specimens heat treated in atmospheric and vacuum environments. The characterization and analysis of the hot-rolled plates considered the crack microstructure and fracture morphology. It was shown that holes appeared along the large angular grain boundaries after annealing at 1100 °C for 8 h. Possible reason: In a high-temperature environment, the decomposition of residual additives in the electrolytic nickel releases oxidizing gases, which oxidizes the grain boundaries. The reaction with carbon diffused into the grain boundaries and produced carbon monoxide gas, which induced holes and severely reduced the grain boundary plasticity. The heat treatment time did not need to be very long for severe grain boundary degradation to occur. After severe cavitation, the electrolytic nickel was severely cracked at grain boundaries cracks due to a shear force, and brittle fractures occurred along grains with very low plasticity.

Research on performance of porous scaffold-based getter activated by induction heating and its application in MEMS device

Non-evaporable getter (NEG) is widely used in vacuum packaging. However, there are two main contradictions. Firstly, the contradiction between bonding temperature of the device and activation temperature of the getter results in the getter being activated first and then packaged, and cannot be repeatedly activated, which seriously reduces the adsorption capacity and life of the getter. Secondly, the contradiction between the small package volume and the large adsorption capacity, how to integrate large adsorption capacity getter in a small space is a tricky problem. In view of the above contradictions, a porous scaffold-based getter activated by induction heating was proposed in this paper, results show that when nickel plating is used as the induction heating layer, the temperature can quickly rise to 700 °C within 10 s, and 1 μm Ti getter can be fully activated for 7 min. The good periodicity of the temperature curves proved that the nickel layer has good repeatable heating characteristics. In addition, the adsorption performance of the getter was tested and characterized at device level. The device level characterization of optical deflection method proves the effectiveness of induction heating to activate getter, which lays a foundation for the application of getter on MEMS devices.

Research on hydrogen distribution of electroless nickel plating on aluminum-based silicon carbide composites

Abstract Aluminum-based silicon carbide composite materials have the characteristics of high thermal conductivity, low thermal expansion, and good dimensional stability. Therefore, the composites are widely used in space microwave component shell products. In order to meet the functional requirements of conductivity, welding, and heat dissipation when applied to antenna microwave components, aluminum-based silicon carbide composite materials need to be chemically plated with nickel, which introduces hydrogen, thus requiring research on hydrogen release and control. Here, SEM, XRD, and other methods are used to characterize the microstructure of aluminum-based silicon carbide substrate and nickel plating layer. There are certain pore structures in both the substrate and plating layer, providing a place for hydrogen storage. The experimental method of hydrogen microprinting has been used to characterize the distribution of hydrogen. The results showed that the hydrogen distribution pattern in aluminum-based silicon carbide nickel plating is as follows: after nickel plating on aluminum-based silicon carbide, hydrogen is distributed in the nickel plating layer and the shallow substrate under the coating; with the extension of time, hydrogen spontaneously diffuses to the deep substrate; hydrogen is mainly distributed in the Al matrix and less on SiC particles.

Enhancing the high-temperature oxidation resistance of C-103 niobium alloy via hybrid treatment combining nickel plating with molten-salt siliconising

ABSTRACT A multi-phase silicide protective coating was prepared by electroplating nickel on the surface of C-103 niobium alloy (89Nb–10Hf–1Ti), followed by molten-salt non-electrolytic siliconising to enhance the high-temperature oxidation resistance of the substrate. The phase composition, microscopic morphology and elemental analysis of the coating were analysed via X-ray diffraction, scanning electron microscope, energy-dispersive spectrometer and hardness distribution. Oxidation characteristics were evaluated by comparing the oxidation inhibition effect of the coating on niobium alloy substrate and that of coating prepared via molten-salt infiltration alone at a constant temperature of 1100°C for 9 h. Results show that a silicide infiltration coating containing about 200-μm-thick compound layer with Ni2Si, NiSi, Nb5Si3, NbSi2, Ni3Si2 and TiNiSi multi-phase composition and ∼10–15-μm-thick diffusion layer were dense with few defects. In the hybrid synthesis process, the upper electroplated nickel coating can promote and modify the growth of subsequent siliconised coating. The duplex prepared silicon infiltration coating can reduce the oxidation rate of niobium alloy substrate by about 1/10, indicating good high-temperature oxidation resistance. This is because the siliconised coating is considerably thick, has a dense blocking structure and generates Ni4Si7Ti4, thereby blocking oxygen.

Electroless Plating of Nanoporous Substrates for Thin Film-Solid Oxide Fuel Cells

Thin-film solid oxide fuel cells (TF-SOFCs) are an attractive renewable energy source due to their high efficiency, increased power output and ability to be efficiently stacked for power generation at a small or large-scale. [N. Q. Minh, J Am Ceram Soc. 1993; 76(3):563-588.] Nanoporous Al2O3, also known as anodized aluminum oxide (AAO) is an appropriate substrate for TF-SOFCs due to its high temperature stability, chemically inert nature, and porosity that allows gas flow to the anode. The aligned, nano-sized pores allow for both conformal sputtering on the surface and efficient fuel delivery to the anode, making it particularly suited for thin film deposition. Electroless nickel plating is used to achieve a fully conductive, nanoporous substrate which catalyzes the hydrogen oxidation reaction and improves current collection efficiency in TF-SOFCs. A minimum plating temperature of 60°C is needed to grow nanoscale Ni deposits into a conductive film without compromising the porosity of the surface. Effective stirring methods are used to deliver the plating solution throughout the high-aspect ratio pores of the AAO substrate and create thru-plane conductivity. To achieve conformal plating, the number of pre-treatment steps was optimized to prevent overplating and create a homogenous Ni deposit. Finally, with the creation of a conformally coated, conductive porous substrate, we can improve the efficiency and power output of TF-SOFC performance with commercially relevant active areas (larger than 1 cm2).

Electroless nickel plating of electropolished and chempolished Additively Manufactured (AM) steel components in various surface orientations

Electroless nickel plating of electropolished and chempolished Additively Manufactured (AM) steel components in various surface orientations

The Effect of the Rare Earth Element Cerium on the Electrocrystallization and Microstructure of Nickel Electrodeposits in Industrial Electrolytes

To meet the industrial production needs for high-quality and precisely controllable structured high-end nickel foils, rare Earth compounds are added as additives in complex industrial electrolytes to improve the quality of the nickel deposition layer. This study investigates the effects of adding rare Earth compounds to the existing industrial production electrolytes (which already contain various organic and inorganic additives in a mixed acid solution) on the surface microstructure, cerium content, grain size, and crystal orientation of the nickel deposition layer. Using direct current electrodeposition, different concentrations of rare Earth compounds were added to the industrial electrolyte, and the cerium content, grain size, and crystal orientation were characterized. The results show that adding 0.8 g·l−1 CeCl3 accelerates the nucleation rate and shortens the nucleation relaxation time. The addition of rare Earth elements promotes multi-directional preferential growth, resulting in uniform and fine grain size, improved grain structure of the deposition layer, and reduced surface roughness of the nickel plating layer. Therefore, rare Earth elements can be used to regulate the structure, microstructure, and grain refinement of the nickel deposition layer without affecting its composition.