Ni-W Alloy Coatings Research Articles

Preparation of MoSi2-particle reinforced Ni-W alloy coatings and their anti-corrosion behavior in CO2-saturated 3.5 % NaCl solution

In the process of oil and gas production, the use of Ni-W electroplated coatings as a protective layer for oil well tubing has been widely used. In this study, the effect of MoSi2 particles as reinforcing material on the properties of electrodeposited coatings was investigated in order to improve the resistance of Ni-W alloy deposits against CO2 corrosion. The purchased MoSi2 sample was subjected to detailed material characterization, including microscopic morphology, crystallographic properties, particle size distribution and dispersion in the plating solution. After the introduction of MoSi2 particles into the deposits, the diffuse phase strengthening mechanism improved the properties of alloy. By comparing the electrochemical behavior of 3.5 % NaCl solution in saturated CO2, it can be concluded that the composite coatings prepared have the best corrosion resistance when MoSi2 is added to the plating solution at 0.02 g/L. This study provides new horizons for the application of Ni-W coatings in CO2-rich environments or CCUS conditions.

Investigation of the influence of nano-CrN concentration on the performance of Ni-W coatings in X80 pipeline steel

A novel nano Ni-W-CrN composite coating was developed for X80 pipeline steel to enhance its structural properties and corrosion resistance. The study explored the effects of varying CrN nanoparticle concentrations (0, 5, 10, 15, 20 g/L) in the deposition solution using techniques such as SEM, EDS, and XRD for analysis and an electrochemical workstation for corrosion testing. The optimal CrN concentration was identified at 10 g/L, resulting in a coating with peak hardness (811HV), low friction coefficient (0.16), minimal wear rate (1.18×10−4 mm3·(N·m)−1), and improved corrosion resistance. This coating significantly outperforms Ni-W alloy coatings in hardness, wear resistance, and elastic recovery, offering a promising approach for enhancing the performance of X80 pipeline steel surfaces.

Enhanced solid particle erosion resistance of nanocrystalline Ni-W coatings through multilayer approach

Electrodeposited nanocrystalline Ni-W alloy coatings are projected as potential alternatives for hard chrome (HCr) coatings owing to their comparable hardness and superior corrosion resistance. However, the limited strain hardening ability of the nanocrystalline Ni-W coatings manifests in their poor resistance towards solid particle erosion involving a high strain-rate (>103 s−1) deformation. In the present study, a novel microstructural engineering strategy has been implemented to enhance the strain hardening ability of the nanocrystalline Ni-W coatings without compromising on their strength/hardness. Ni-W multilayer coatings composed of alternatively stacked soft (2.6 GPa) and hard (8.5 GPa) Ni-W layers were developed using the pulse reverse electrodeposition technique. Further, to investigate the effect of individual layer thickness (λ), multilayer coatings with different λ were deposited. Solid particle erosion testing using the angular SiO2 particles showed that the multilayer coatings (irrespective of λ) exhibit superior erosion resistance compared to the homogeneous nanocrystalline Ni-15W at both oblique (θ = 30°) and normal (θ = 90°) impact conditions. The post-erosion microstructural analysis of the multilayer coatings revealed that the hard Ni-W layers undergo uniform strain (ε > 50 %) without cracking due to the constrained co-deformation imposed by the surrounding soft Ni-W layers. Therefore, the enhanced erosion resistance of the multilayer coatings is attributed to the effective dissipation of impact energy through co-deformation of the individual hard and soft Ni-W layers.

Influence of pulse parameters on microstructure and corrosion characteristics of electrodeposited Ni-W alloy coating

Material characterization and electrochemical performance of the pulse plated Ni-W alloy coatings were assessed by varying duty cycles (0–50%) and pulse frequencies (10–500 Hz) under relatively low applied current density (0.1 mA·cm−2). Compared to DC electroplating, the pulse plating process exhibited lower cathodic current efficiency, and the obtained coatings displayed slightly lower W content. However, the surface roughness, hardness, and anti-corrosion properties of the coatings were improved due to common characteristics, such as grain refinement, fewer defects, and enhanced surface uniformity, associated with the pulse plating process. The Ni-W alloy coating produced at a medium pulse frequency of 100 Hz with duty cycles of 10% and 50% exhibited the highest hardness (5.34±0.33 GPa) and the best corrosion resistance (corrosion current density Ic: 9.62 μA·cm−2), respectively. These properties were significantly improved compared to those for the counterparts prepared by DC electroplating (hardness: 3.13±0.58 GPa; Ic: 10.89 μA·cm−2).

The Effect of Heat Treatment on Phase Structure and Mechanical and Corrosion Resistance Properties of High Tungsten Ni-W Alloy Coating

The present study investigated the surface morphology, phase composition, mechanical properties, and corrosion resistance of Ni-W alloy coatings prepared under current densities of 1–5 A/dm², after undergoing heat treatment at 400 °C, 600 °C, and 900 °C. The grain size of the as-plated Ni-W alloy coating was below 10 nm. After heat treatment at different temperatures, the grain size increased, reaching a maximum value of around 30 nm at 900 °C. Heat treatment crystallized and altered the structure of the coating. Different heat treatment temperatures yielded different precipitates, including Ni4W, Ni6W6C, and WC. The highest coating hardness (820–940 Hv) was achieved at 400 °C, while the best corrosion resistance was achieved at 600 °C. The precipitation hardening phase can be obtained by proper heat treatment temperature, yielding the desired properties of the composite coating.

(Invited) Nanocrystalline Ni-W: The Science, Commercialization and Scaling of an Electrodeposited Coating

Nanocrystalline Ni-W alloy coatings deposited using pulse-reverse electrodeposition were studied as a model nanocrystalline material 20 years ago at MIT, and commercialized by Xtalic Corporation in electronic applications beginning in 2008. Under the trade name Xtronic, these coatings provide exceptional wear resistance and barrier protection due to their extremely fine ~10 nm grain size, and have enabled significant reconfigurations of the electronic connector metallization stack in many applications from enterprise to consumer electronics. This talk will review the basic science of the Ni-W alloy system and its ability to deliver these unique properties by virtue of its nanostructure, as well as some of the electrochemical features of the process that enabled its scaling from the laboratory to hundreds of billions of individual metallized contacts. As a case study in the growth of an electrochemical nanotechnology, the talk will also review elements of technology transfer between MIT and Xtalic Corporation that helped facilitate Xtronic’s commercial emergence, including intellectual property management and ongoing basic research.

Switching Properties of the Contact Coatings Based on Refractory Metals Alloys

Switching the properties of the Ag contact groups of an electromagnetic relay with the electrodeposited Ni-W and Co-W alloy coatings was studied. It is shown that these coatings are able to stabilize the spread of contact resistance within the entire test interval and to increase the service life of Ag contact groups from 2.3 × 106 to 4.5 × 106 commutation cycles. According to our research, the service life of coated contact groups is mainly determined by a change in the surface morphology caused by the electrical erosive transfer of the contact materials and to a lesser extent by the formation of poorly conductive adsorbed hydrocarbon films.

Excellent Properties of Ni-15 wt.% W Alloy Electrodeposited from a Low-Temperature Pyrophosphate System

Electrodeposited Ni-W alloy coatings are considered to be one of the most suitable candidate coatings to replace carcinogenic hexavalent chromium coatings. In this work, Ni-W alloys are electrodeposited from pyrophosphate baths containing different concentrations of Na2WO4 2H2O (CW) at 40 °C. Both CW and the applied current density can affect the W content in the coatings. The effect of CW becomes weaker with the increased current density. The Ni-W alloys with 15 ± 5 wt.% W (Ni-15 wt.% W) are obtained from the bath containing 40 g L−1 CW at a high current of 8 A dm−2. The microhardness, corrosion resistance and hydrogen evolution reaction (HER) are measured with a microhardness tester and an electrochemical workstation. The modified properties are studied by heat treatment from 200 to 700 °C. The highest microhardness of 895.62 HV and the better HER property is presented after heat treatment at 400 °C, while the best corrosion resistance in 3.5 wt.% NaCl solution appears at 600 °C.

Electrodeposition of multilayer NiW alloy coating for improved anticorrosion performance

The attractiveness of electroplating linked to cathodic current density (CD) has tried to exploit here to the development of coatings of high corrosion resistance. Multilayer NiW alloy coatings of better anticorrosion performance were electrodeposited from a tartrate bath by periodic pulsing of CD between two values, during the process of deposition. The multilayer coatings of different configurations, in terms of composition and thickness of individual layers were developed by proper modulation of amplitude and duration of the square current pulse, respectively. The deposition conditions were optimized for best performance of the coatings against corrosion. Our experimental study revealed that under optimal condition, multilayer NiW coating having (NiW)1.0/3.0/120 configuration is almost six times more corrosion resistant than its monolayer coating, deposited from same bath for same duration. The reason for improved corrosion performance in multilayer NiW alloy coating was explained in the light of effect of larger interfaces affected due to layered deposition and confirmed by scanning electron microscopy analysis, energy dispersive spectroscopy and X-ray diffraction study. The mechanism of corrosion responsible for its better performance, in relation to its monolayer coating is given, and results are discussed.

Preparation and tribological research of the electrodeposited Ni[sbnd]W alloy coatings for piston ring application

This study determines the effect of the electrodeposition process parameters on the composition, mechanical properties and wear resistance of NiW alloy coatings. The optimum conditions for the electrodeposition of a NiW alloy coating on a piston ring to increase resistance to wear and friction are determined. The results show that the content of tungsten (W) in the NiW alloy coatings is between 23.8 wt% and 42.2 wt%, depending on the DC current density and the concentration of the sodium tungstate in the electrolyte. The best mechanical properties are obtained for Ni-40.6 wt% W alloy that is annealed at 600 °C for 1 h. The tribological properties of the coating are determined using a pin-on-disk abrader tester under SAE 10W40 lubricated conditions. The tribological study shows that Ni-40.6 wt%W coating that is annealed at 600 °C for 1 h features a lower coefficient of friction and better anti-wear characteristics than a hard chromium coating that is currently widely used as a coating for piston rings. The resistance of a Ni-40.6 wt%W alloy coating for piston rings to wear and scratching is studied using a 125 cc, single-cylinder, air-cooled engine. The results show that the Ni-40.6 wt%W coating has good resistance to wear and scratching.

Electrocatalytic properties of pulse plated Ni-W alloy coatings in alkaline electrolytes

ABSTRACT Ni-W electrodes with differing tungsten content as electrocatalysts for the hydrogen evolution reaction (HER) were prepared by pulse plating. The structural and morphological characterisations of the electrodes were analysed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), respectively. The electrocatalytic activity for the HER has been evaluated using chronopotentiometry, cathodic polarisation, and cyclic voltammetry techniques. Addition of tungsten in the electrode contributes to enhancement of electrocatalytic performance by the degree of increased amorphisation of structure.

Current Status of Research on Electrodeposited Ni-W Alloy Coating

This paper discusses the influence of pH value, temperature and current density on the crystalline and amorphous structure of Ni-W alloy coatings during the electroplating process. The relationship between the corrosion resistance of Ni-W alloy coating and its crystal structure is discussed. In addition, the most common types of ternary systems and composite coatings for electrodeposited Ni-W alloy coatings are introduced. The effects of element types and contents on the hardness, wear resistance, corrosion resistance and thermal stability of Ni-W alloy coatings are analyzed. Finally, the current problems and development directions of Ni-W alloy coatings are proposed.

Development of Ni-W alloy coatings and their electrocatalytic activity for water splitting reaction

This study reports the electrodeposition of Nickel-Tungsten (Ni-W) alloy coatings and their efficiency as electrode material for water splitting applications. Ni-W alloy coatings were electrodeposited and their electrocatalytic activity towards alkaline water splitting for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in 1 M KOH were studied. Cyclic voltammetry (CV) and chronopotentiometry (CP)techniques were used to quantify their electrocatalytic behaviors. It demonstrated the inverse dependency of electrocatalytic behaviors of coatings towards HER and OER at low and high c.d.'s, respectively. This is attributed to the change in the composition, in terms of Ni and W content of the alloy. The surface features, structural and compositional change of coatings, responsible for improved electrocatalytic activity were examined using Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Energy dispersive X-ray spectroscopy (EDS) techniques. Experiment results revealed that alloy deposit can be used as a potential material for water splitting applications.

Corrosion Resistance of Heat-Treated Ni-W Alloy Coatings.

The paper presents research on evaluation of corrosion resistance of Ni-W alloy coatings subjected to heat treatment. The corrosion resistance was tested in 5% NaCl solution by the use of potentiodynamic polarization technique and electrochemical impedance spectroscopy. Characteristics of the Ni-W coatings after heat treatment were carried out using scanning electron microscopy, scanning Kelvin probe technique and X-ray diffraction. Suggested reasons for the improvement of properties of the heat treated Ni-W coating, obtained at the lowest current density value (125 mA∙cm−2), are the highest tungsten content (c.a. 25 at.%) as well as the smallest and the most homogeneous electrochemically active surface area.

Influence of Positional Isomeric Spacers of Naphthalene Derivatives on Ni-W Alloy Electrodeposition: Electrochemical and Microstructural Properties.

Herein, Ni–W alloy matrixes were successfully fortified with two salen-type Schiff bases 1-((E)-(2-((E)-(2-hydroxynaphthalen-1-yl)methyleneamino)phenylimino)methyl)naphthalen-2-ol (OPD) and 1-((E)-(2-((E)-(2-hydroxynaphthalen-1-yl)methyleneamino)phenylimino)methyl)naphthalen-2-ol (PPD) as additives, of similar molecular structure but varied isomeric spacers, using a facile direct current electrodeposition technique. The resulting coatings from the additive-introduced reaction system were termed as Ni–W/OPD and Ni–W/PPD throughout the study. The deterioration process (0.5 M H2SO4), surface properties, elemental composition, functional groups, and structurs of the resultant coatings were analyzed by means of Tafel and electrochemical impedance spectroscopy, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy, atomic force microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction (XRD). The bare Ni–W alloy deposition resulted in a loose microstructure with higher porosity density (12.2%), while that of additive-doped plating electrolytes resulted in a compact and dense microstructure with lesser porosity density (6.3%) and minimal porosity density (3.7%) as for Ni–W/OPD and Ni–W/PPD alloy coatings, respectively. Improved corrosion parameters presented superior corrosion characteristics of Ni–W alloy coatings from an additive (PPD)-induced bath, i.e., Ni–W/PPD. Synergetic adsorption of imine groups (N atoms), hydroxyl groups (O atoms), and aromatic electron clouds and reduction in steric hindrance produced by a larger isomeric spacer strengthened the surface adsorption of additives, yielding a fine nanocrystalline Ni–W coating with reduced porosity and well-refined grains, implying the outstanding shielding effect. Results of FESEM, AFM, and XRD analyses revealed a complete cohesion between two neighboring islands, resulting in a fine planar structure with minimal coating defects for Ni–W/PPD coatings, authenticating the corrosion parameters.

A Research on Niw Alloy Coatings on Mild Steel through Electrodeposition Method

In order to enhance the structural and mechanical properties of mild steel, NiW nanocrystalline thin layer has been coated on the surface of mild steel through electroplating technique at bath temperature of 40 C over the deposition time of 45 minutes. The nanocrystalline NiW alloy coatings were deposited on mild steel at constant current density of 1 A/dm2 . The structural and chemical characterizations of the NiW alloy coated mild steel were performed by scanning electron microscopy (SEM) and X-ray diffraction pattern (XRD). The micro hardness value of the coated mild steel was determined by using Vickers Hardness test. The effect of NiW on wear behavior of mild steel was analyzed using Pin-on-disc apparatus. The mechanical properties of mild steel such as hardness, roughness and wear resistance have been enhanced in an appreciable manner. This is primarily due to the NiW alloy coatings on mild steel. The variations in structural and mechanical properties of NiW coated mild steel were also studied

Anti-corrosion and microstructural properties of Ni–W alloy coatings: effect of 3,4-Dihydroxybenzaldehyde

In the present work impact of 3,4-Dihydroxybenzaldehyde on the microstructural and corrosion behavior of nanocrystalline Ni-W alloy coatings has been elucidated. A systematic investigation on the protection ability of Ni-W alloy coatings in 0.2 M H2SO4 solution was done with the aid of tafel polarization curves and electrochemical impedance spectroscopy (EIS) studies. Corrosion performance of the alloy films obtained in the absence and in the presence of different concentrations of 3,4-Dihydroxybenzaldehyde (0–500 ppm) in the bath was explained in the light of additive concentration. Compared to the blank and other concentrations of additive, 250 ppm of additive containing bath was predicted as the most promising one for the introduced citrate based Ni-W alloy electrodeposition. Low corrosion rate (0.06 mm/year) and high charge transfer resistance (2505.3 Ω cm2), for the electrodeposits, obtained from the bath containing 250 ppm of 3,4-Dihydroxybenzaldehyde supports for its high anticorrosion performance. The marked difference in the corrosion resistance property is ascribed to the formation of fine-grained deposits, smooth surface, and inclusion or adsorption of additive within the deposits in the presence of the additive (250 ppm) in the bath. Further, the adsorption of additive molecules on the metal surface was explored with the help of quantum chemical calculations based on DFT.

Study on Mechanical and Anticorrosion Performance of NiW Alloy Coatings Prepared by Induced Codeposition

Study on Mechanical and Anticorrosion Performance of NiW Alloy Coatings Prepared by Induced Codeposition

Pulse and Pulse Reverse Electrodeposition of Cubic, Tetragonal and Its Mixed Phase of Ni-W Alloys for Corrosion Applications

Ni-W alloy coatings on mild steel substrate with various crystalline structures were prepared using pulse and pulse reverse electrodeposition method for corrosion protection application. The co-deposition behavior of tungsten and basic electrochemical information of electrolytes were confirmed through cyclic voltammetry studies. The crystalline nature, alloy phase and it is crystal (cubic and tetragonal) phase transformations were confirmed using X-ray diffractions. The corrosion resistance performances of the deposits were studied using Tafel polarization and electrochemical impedance studies. Correlation between the crystal structures and its corrosion resistance performance were explored and tetragonal Ni-W alloy film having better corrosion resistance than cubic Ni-W alloy film. The mixed phase of tetragonal dominated cubic structures in the alloy matrix has the superior corrosion resistance performance. This study confirms the Ni-W alloy films have good corrosion protection and this can be tuned with the modification of crystal structure using various deposition conditions.

Sliding wear of as-deposited and heat-treated nanocrystalline nickel-tungsten alloy coatings

The aim of the present study is to understand the sliding wear response of pulse electrodeposited nanocrystalline nickel (Ni) – tungsten (W) alloy coatings in both as-deposited and heat-treated conditions. Ni-W alloy coatings with a wide range of W content (0% to 25 at%) were deposited using pulse electrodeposition and subsequently annealed at 700 °C up to 1 h. The tribological behaviour of Ni and Ni-W coatings (both as-deposited and heat-treated) was studied using a unidirectional pin-on-disc configuration at two different normal loads 3 kg and 5 kg respectively. All tests were performed in atmospheric air, at room temperature and at a constant sliding speed of 0.67 m s−1 using WC-Co disc as countersurface. Wear test results indicated that Ni-W alloy coatings exhibit greater wear resistance when compared to pure Ni coatings at both the loads. The wear mechanism in pure Ni coatings was attributed to severe abrasive wear along with brittle fracture whereas Ni-W alloy coatings exhibited mild ductile wear characterized by micro-ploughing. In the case of as-deposited Ni-W alloy coatings, the addition of W up to 17 at% increased the wear resistance due to improvement in hardness, however, further increase in W content resulted in amorphization and reduced the hardness with corresponding decrement in wear resistance. Heat treatment of coatings resulted in grain growth, crystallization of amorphous phase and precipitation of nanoprecipitates (beyond 12 at% W). Presence of nanoprecipitates and crystallization of amorphous phase resulted in significant improvement in wear resistance of the heat-treated coatings compared to their as-deposited counterparts. Addition of W to Ni did not vary the coefficient of friction (CoF) significantly and was found to be independent of W content, load and hardness of the coatings. The effect of load and hardness of the coatings on wear rate did not follow the wear relationship proposed by Archard.