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Electroless plating treatment is one surface modification technique. An added effect due to electroless plating is expected, and the vibration damping capacity of the structures may be improved by this technique. In the present study, the vibration damping capacity of such electroless plated structures is measured experimentally. Damping capacity can be improved regardless of the plated film materials. Improvement efficiency with an electroless plating film with dispersed foreign particles such as SiC ceramics is higher than with a uniform electroless plating film.

The purpose of this paper is to investigate the deposition of uniform, adherent and crack‐free Ni‐P thin films on carbon fibres using the electroless deposition technique.

Before applying the electroless process, the carbon fibre surfaces must be subjected to several treatment processes to remove the organic binder, etching and surface metallization. The surface morphology of the Ni‐P coatings was assessed using a scanning electron microscope (SEM). The chemical compositions of Ni‐P layers were identified by energy dispersive X‐ray analysis (EDS). The bond strength of the coated layer was determined by measuring the electrical resistance at the fibre/coating interface. The magnetic properties of the fibres were estimated using a hysteresis diagram. The tensile performance of single fibres coated by Ni‐P has been investigated with respect to coating thickness.

Pre‐treatment processes are used to improve the adhesion of Ni‐P layers and to obtain homogeneous coatings. The influence of plating parameters (temperature, pH and time) on the coating thickness of the Ni‐P layer was investigated. It was found that the coating thickness increased as the pH value, plating time and the temperature of the bath increased. The results revealed that a complete and uniform Ni‐P coating on fibre could be obtained at optimum conditions 85°C, pH 6, for 60 min, and the results indicated that the P content in the electroless deposit is approximately 3.4 wt%. The tensile strength values are improved significantly after coating and increased by 3‐5 times with increasing of coating thickness from 0.3 to 2 μm.

The results presented in this work are an insight into understanding of the deposition and adherence of Ni‐P thin films on carbon fibre using the electroless technique and behaviour of the coated fibre.

This paper presents an experimental study to assess the reliability of solder ball attachment to the bond pads of PBGA substrate for various plating schemes. The basic structure of the under bump metallisation is Cu/Ni/Au. Three different kinds of electroless plating solutions are used to deposit the Ni layer, namely, Ni‐B, Ni‐P (5 per cent), and Ni‐P (10 per cent). Also, conventional electrolytic Ni/Au plating is performed to provide a benchmark. After solder ball attachment, mechanical tests are conducted to characterize the ball shear strength for comparison. Furthermore, some specimens are subjected to multiple reflows to investigate the thermal aging effect.

Different types of wood (ash, oak and beech) have been activated by new activation method. The aim of this work is to study the effect of different types of wood on the physical and chemical properties of Ni/Pd coatings.

The wood was activated by ablation of the Pd target using pulsed laser deposition (PLD) technique. Different diagnostic techniques such as X-ray photoelectron spectroscopy (XPS), attenuated total reflection (ATR) spectroscopy and energy dispersed X-ray spectroscopy (EDS), in parallel with scanning electron microscopy (SEM) were used to achieve this goal.

The XPS technique confirmed that the highest concentration of Pd was found in the Pd/beech sample, which is associated to the texture of the beech wood substrate surface. EDS results confirmed the absence of any contamination related to electroless plating method. It is concluded that the wood morphology and its surface roughness play a conclusive role to obtain different quantity of metal by PLD and electroless plating methods.

Although several works have been performed to study the influence of substrates on the coated metals and away of the traditional methods in activating non-catalytic surface, in this paper, PLD method is used to obtain a good quantity of Pd distributed on the entire surface and inside the porous of the wood. This study could be considered as a step investigation for understanding the role of the wood substrate morphology on the physical and chemical properties of films. To our knowledge, there are no works of combining a coated Ni/Pd by electroless plating and PLD methods on wood.

In this study, we examined the improvements in friction and wear properties between steels for aircraft parts, resulting from the surface modifications with electroless plating film and amorphous carbon coating or diamond‐like carbon (DLC) coating. Friction and wear properties are measured using a pin‐on‐flat wear‐testing machine with reciprocating sliding. From measurements of the coefficient of friction and wear amount, observations during sliding motion and visual inspection of wear traces, the following was clarified. A remarkable improvement of friction and wear properties is realized by DLC coating. Electroless plating increased the hardness of the plated surface considerably. However, it does not contribute to improved friction and wear properties.

This paper aims to coat ternary composite NiBP-graphite films by Dynamic Chemical Plating “DCP” technique with a growth rate of at least 5 μm/h, which makes this technique a worthy candidate for production of composite films. Electroless nickel plating method can be used to deposit nickel–phosphorous and nickel–boron coatings on metals or plastic surface. However, restrictions such as toxicity, short lifetime of the plating-bath and limited plating rate have limited applications of conventional electroless processes.

DCP is an alternative for producing metallic deposits on non-conductive materials and can be considered as a modified electroless coating process. Using a double-nozzle gun, two different solutions containing the precursors are sprayed simultaneously and separately onto the surface. With this technique, NiBP-graphite films are fabricated and their corrosion and tribological properties are investigated.

With a film thickness of 2 μm, tribological analysis confirms that these coatings have favorable anti-friction and anti-wear properties. Corrosion resistance of NiBP-graphite composite films was investigated, and it was found that graphite incorporation significantly enhances corrosion resistance of NiBP films.

DCP is faster and simpler to perform compared to other electroless deposition techniques. Using a double-nozzle gun, metal salt solution and reducing agents are sprayed to the surface, forming a deposit. Previously, coatings such as Cu, Cu-graphite, Cu-PTFE, Ni-B-TiO2, Ni-P, Ni-B-P and Ni-B-Zn with favorable compactness and adherence by DCP were reported. In this paper, the authors report the application of the DCP technique for depositing NiBP-PTFE nanocomposite films.

Nickel phosphorus (Ni−P) thin-films have been electrolessly deposited in an acid-plating bath with the addition of manganese sulfate monohydrate (MSM) to achieve higher resistance for the application of embedded resistor with value beyond 10 KΩ. As this material is being used for fabricating embedded resistors under the addition of MSM, its resistance properties including effects of MSM concentration and plating time on resistances, temperature coefficient of resistance (TCR), and resistance tolerance of embedded resistor were investigated. The paper aims to discuss these issues.

The structure of fabricated Ni−P film was detected by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The properties of substrate, including the surface morphologies, glass transition process and boundary of copper pad and substrate surface, were performed by SEM, dynamic mechanical analysis and optical microscope, respectively. The resistance tolerances of embedded resistors were elaborated from the cases of Ni−P thin-film resistance tolerance and the size effects of resistors, respectively.

The fabricated film was found to be constructed with numerous Ni−P amorphous nanoparticles, which was believed to be the reason of increasing thin-film resistance. The Ni−P thin-films presented over one magnitude order of resistance increasing in the case of MSM concentration varied from 0 to 40 g/L. For the case of TCRs, Ni−P thin-films deposited with 20 g/L MSM exhibited low TCRs of within ±100 ppm/°C Before TR at temperature elevating from 40 to 160°C, indicating that this Ni−P thin-film belongs to the constant TCR materials according to the military standard. For the tolerance of embedded resistor, the tolerance contributed by Ni−P thin-film was obtained to be 9.8 percent, whereas the geometry tolerances were in the range of 0-20 percent according to the geometries of embedded resistor.

For Ni−P thin-film without MSM, its low resistance with around 100 ohm/sq. limit the values of resistor few KΩ and restricted its widespread application of embedded resistor with higher resistance beyond 10 KΩ. The authors introduced MnSO₄ in Ni−P electroless plating process to improve the low resistance of Ni−P thin-film. The resistance was increased over one order of magnitude after added with 40 g/L MnSO₄. Due to the specific structure, as this material is being used for fabricating embedded resistors, the electrical properties and its application properties to verify its appliance in embedded resistor were systematically investigated by means of SEM, TEM, XRD characterizations, TCRs, resistance tolerance analysis, respectively.

The purpose of the current study is to explore the potential possibility of acceleration in recognition, remedial process of heart disease and continuous electrocardiogram (ECG) signal acquisition. The textile-based ECG electrode is prepared by inkjet printing of activator followed by electroless plating of nickel (Ni) particle.

The electrical resistance shows a range of around 0.1 Ω/sq, which sounds quite proper for ECG signal acquisition, as the potential difference according to heart activity on skin surface is in milivolt range. Surface modifications of Ni–phosphorus (P)-plated polyester fiber were studied by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffractionmethods. The quality of the acquired signal from printed square-shaped sensors in two sizes with areas of 9 and 16 cm2 compared with the standard Ag/Agcl electrode using commercial ECG with the patient in the sitting position.

Comparison of these data led to the consideration of small fabric sensor for better performance and the least disturbance regarding homogeneity and attenuation in electric field scattering. Using these types of sensors in textile surface because of flexibility will provide more freedom of action to the user. Wearable ECG can be applied to solve the problems of the aging population, increasing demand for health services and lack of medical expert.

In the present research, a convenient, inexpensive and reproducible method for the patterning of Ni features on commercial polyester fabric was investigated. Printed designs with high electrical conductivity can be used as a cardiac receiving signals’ sensor.

The ability to produce a uniform composition, high corrosion resistance with a hard coating layer during the electroless coating techniques are mainly based on the plating bath composition. The complexing agent is one of the most important components that control the coating layer properties. This paper aims to investigate the effect of the glycine as a complex agent on the surface and corrosion properties of Ni-P and Ni-P/Al₂O₃ electroless coating.

In this study, the effect of glycine as a complexing agent on the final surface and corrosion properties of the Ni-P and Ni-P/Al₂O₃ coatings has been investigated. The surface morphology and composition of the coated samples were investigated by scanning electron microscope (SEM) imaging and energy dispersive x-ray spectroscopy (EDS) analysis. Linear polarization scan and electrochemical impedance spectroscopy techniques were used to investigate the corrosion properties of the coating layer.

The results clarify that, glycine has a remarkable effect on the porosity content of Ni-P and Ni-P/Al₂O₃. It was found that increasing of glycine concentration results in higher porosity content in the coating layers. Also, the porosity in the coating layers minimizes the protectability of the coating against corrosion. The results also show that adding nano-alumina (Al₂O₃) to the coating path has improved the corrosion properties by decreasing the porosity in the coating layer. The scanning electron microscope (SEM) images showed that the concentration of glycine affects the content and distribution of alumina nanoparticles embedded in the coating layer. Also, it was observed that using a high concentration of glycine (0.4 M glycine), the alumina tends to agglomerate and the final alumina content in the coating was decreased.

The present study reveals that the quality of the final coating plays a major role in the corrosion performance of the steel substrate. The coating quality can by improve remarkably by optimization of the complexing agent used in the plating bath, to minimize the porosity involve in the coating layer.

This study aims to elucidate the reaction mechanism of electroless NiP deposits on conductive but non-catalytic Cu films on the basis of their nucleation and growth without Pd catalyst and to measure the deposition rate and activation energy of electroless NiP deposits on the non-catalytic Cu film at various deposition times (60, 120, 240 and 480 s) and temperatures (70, 80 and 90°C) at pH 4.6.

Specimens with and without Pd catalyst on Cu film were prepared as follows: the Pd catalyst was deposited on half of the Cu film using a deposition protector, and the specimen containing the Pd catalyst deposited on half of its area was immersed in electroless NiP solution. The growth of NiP on the Cu films with and without the Pd catalyst was observed.

The number of Pd nanoparticles increased with Pd activation time; the nucleation of Pd dominated over growth at 60 s. Lattice images show that the d-spacing of Ni nanoparticles doped with less than 10 at% P increased to 2.050 Å. Nucleation of NiP deposits occurred simultaneously in the specimens with and without the Pd catalyst, because electrons could be transferred via the conductive Cu. Therefore, the reaction mechanism of the electroless NiP deposited on Cu film appears to be electrochemical. The activation energies for NiP deposits (15 s Pd with catalytic Pd, 15 s Pd without catalytic Pd, 60 s Pd with catalytic Pd and 60 s Pd without catalytic Pd) on the Cu film are 65.8, 64.0, 64.3 and 58.1 kJ/mol, respectively. This demonstrates that, regardless of the volume and the presence of catalytic Pd, the activation energy of electroless NiP has a consistent value.

It is necessary to study the relationship between the volume of Pd nanoparticles and the nucleation rate of NiP at an initial stage, as there are limited data regarding the effect of Pd volume on the nucleation rate of NiP.

The reaction mechanism of the electroless NiP deposited on conductive but non-catalytic Cu film involves electrochemical reactions because the nucleation of NiP deposits occurs on conductive Cu film regardless of the presence of the Pd catalyst.