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The purpose of this paper is to evaluate the use of nickel and nickel oxide thin films as anticorrosive protection for low‐carbon steel when expose to sour media. The purpose of this paper is also the study of a superior oxide nickel thin film over the nickel thin film.

Nickel thin films are applied on steel AISI 1018 (UNS G 10180) by magnetron sputtering and electrolytic techniques. The films are tested after deposition on low‐carbon steel. A massive nickel electrode also is evaluated as a reference. In order to evaluate the protective properties of films in sour media, electrochemical techniques are employed, but also scanning electron microscopy in order to identify the difference in porosity and surface of the films coated by both techniques.

Micrographs of thin films deposited by magnetron sputtering reveal a homogeneous surface whereas the electrolytic films show many micro‐crevices and expose the substrate even on the oxide films. These results indicate that localize corrosion on the film surface diminishes the corrosion resistance, even if the film itself has a superior corrosion resistance.

These kinds of nickel thin films deposit by magnetron sputtering and their oxides are an excellent anticorrosion alternative even for mild carbon steel exposed on sour media.

The sputtered nickel deposit is consistently more protective against corrosion than an electrolytic deposit of the same thickness. The nickel oxide benefits the steel by displacement of the corrosion potential towards more positive values. The electrochemical performance of solid nickel oxide is superior compared to the nickel metallic film on the steel substrate.

The first major nickel alloy introduced to the industry, about 100 years ago, was a Ni‐Cu alloy 400. This alloy is still widely used in a variety of industries and will continue to be used in this current century. Over the past 100 years, especially in the last 50 years, improvements in alloy metallurgy, melting technology, and thermo‐mechanical processing, along with a better fundamental understanding of the role of various alloying elements has led to new nickel alloys. These have not only extended the range of usefulness of existing alloys by overcoming their limitations, but are reliable and cost‐effective and have opened new areas of applications. This paper briefly describes the various nickel alloy systems developed during the last 100 years and comments on what the future holds for the newer alloys developed in the last 20 years and on the competition faced by these alloys in the new millennium. High‐temperature alloys are not discussed in this paper.

This study aims to investigate the effect of changes in iron content in 70/30 copper–nickel alloy on the corrosion process.

70Copper–30Nickel-xFe-1Mn (x = 0.4,0.6,0.8,1.0 Wt.%) alloy were prepared by the high frequency induction melting furnace. The scanning electron microscope, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy were used to analyze the morphology and component of the corrosion product film.

The results show that the corrosion resistance of 70/30 copper–nickel alloy added with 1.0%Fe is the best, and the film is divided into inner dense Cu2O composite film and outer hydration loose layer; XRD showed that after adding 1.0% Fe, the content of Cu2(OH)3Cl in the corrosion product film was significantly reduced, while the content of Cu2O remained unchanged; XPS showed that nickel accumulates in the inner layer of corrosion product film; the stage growth mode of the film, the role of nickel in it and the enrichment mechanism of iron in the inner film were summarized and discussed.

The changes in the composition and structure of the corrosion product film caused by the iron content are revealed, and the mechanism of the difference in corrosion resistance is discussed.

This paper aims to search the optimum content of Ni on the microstructure, phase and electrochemical behavior of high-strength low alloy (HSLA) steel in the 3.5 wt.% NaCl solution.

The microstructure and corrosion resistance of Ni-containing HSLA steel in the simulated marine environment was studied by optical microscopy, scanning electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical techniques.

The sample containing 3.55 wt.% of nickel exhibited a finer grain size of 10 μm and a lower i_corr of 2.169 µA cm⁻². The XRD patterns showed that the Fe-Cr-Ni solid solution, FeC and Cr₃C₂ were observed in samples when Ni was added. Besides, the 3.55 wt.% of nickel addition enhanced the charge transfer resistance of the low alloy steel which suggested the sample possessed excellent inhibition of electrochemical reaction and corrosion resistance. The XPS spectrum suggested that nickel was beneficial to improve the corrosion resistance of steel by forming protective oxides, and the ratio of Fe²⁺/Fe³⁺ in protective oxides was increased.

Finding the comprehensive performance of HSLA steel which can be applied to unmanned surface vehicles in marine operations.

This study has a guiding significance for optimizing the composition of HSLA steel in a Cl- containing environment.

This paper aims to examine the performance of low-pressure cold-sprayed zinc–nickel (Zn-Ni) composites coating, i.e. whether it has the same performance as Zn-Ni alloy coating.

In this paper, Zn-Ni composites coatings containing four different nickel contents were prepared with commercial DYMET 413 low-pressure cold spraying system under the same parameters. Corrosion behaviors of four kinds of coatings were examined with potentiodynamic polarization curves and electrochemical impedance spectroscopy methods, combined with scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction.

Corrosion behavior of Zn-Ni composites coating is similar to Zn-Ni alloy coating. In the early stages of immersion, the anodic dissolution of zinc happens, which results in the formation of a zinc hydroxide layer. With the continuous infiltration of chloride ion, zinc hydroxide will get converted to zinc oxide, basic zinc chloride and basic zinc carbonate. The presence of nickel in coatings can prevent zinc hydroxide from converting into zinc oxide.

Further research should be done on improving the deposition efficiency, as the deposition efficiency of low-pressure cold spray is lower than 30 per cent.

Low-pressure cold spray coating can be used in cyclic dry/wet conditions to prolong the life of a steel structure.

Low-pressure cold spray Zn-Ni coating is an environmentally friendly anticorrosion method which can be used as an alternative of hexavalent chromium passivation coating.

Zn-Ni composite coating can be deposited on steel directly by low-pressure cold spray by mechanically mixing the powders together. The composite coating also has the same long-term anticorrosion performance as Zn-Ni alloy coating.

The purpose of this paper is to present a better understanding of nickel corrosion, also known as “black pad” during gold deposition of EN1G.

This paper presents an accumulation of personal experience and observations of the problem over a period of ten years. It incorporates the experience of the Global Trade Association connecting the electronic industries (IPC) plating committee as it set out to write the IPC electroless nickel‐immersion gold (ENIG) specification‐4552.

Understanding how corrosion occurs will go a long way in helping printed circuit board (PCB) manufacturers stay clear of the issue and make high quality ENIG finished PCBs.

The majority of the data presented has been substantiated.

The paper details how, by good understanding of the mechanism of formation of corrosion products, manufacturers can steer clear from the problem.

The Kanigen process of nickel deposition by catalytic chemical reduction is a practical production method for uniformly coating metals and non‐metals with a layer of hard, corrosion‐resistant amorphous nickel‐phosphorus alloy. This process has made available to industry a material with new and considerably improved surface properties. Both the technique and the product are unique. The amorphous high‐nickel low‐phosphorus alloy is deposited at a uniform rate on the piece being coated wherever it is in contact with the hot solution and whatever the shape. The non‐porous coating is hard but relatively brittle, adheres well to most properly pretreated basis materials, and has improved corrosion resistance (compared to pure nickel) which can be increased further by heat treatment.

The cathodic polarization of Ni in hydrochloric acid solutions has been investigated using the galvanostatic technique. The rate of hydrogen evolution reaction was found to depend on the concentration and pH of the solution. The reaction order with respect to hydrogen ion was found to be one. The rise of temperature enhances the rate of hydrogen evolution reaction. The activation energy, \triangleH*, for such process was found to be 10kcal. mol^‐1. The effect of aniline and some of its derivatives (o‐, m‐ and p‐anisidine) on the cathodic polarization of nickel in 1M HCl solution was also studied. These compounds were found to inhibit the rate of hydrogen evolution reaction without affect on its mechanism. The inhibition efficiency depended on the concentration and type of the inhibitor. The inhibition efficiency ranged between 73 and 92 per cent at the highest concentration (10^‐2M), and ranged between 24 and 60 per cent at the lowest concentration (10^‐4M). This corresponded to surface coverage of the metal by the inhibitor. The degrees of surface coverage, θ, were calculated and found to increase with the inhibitor concentration. The results show also that, the inhibitors were adsorbed on the nickel surface according to Langmuir adsorption isotherm.

Nickel–gold planar surface coatings have been increasingly specified over the last ten years as the circuit board solderable finish of choice. Although offering a number of significant advantages over both conventional Hot Air Solder Levelled (HASL) finishes and alternative planar finishes, nickel–gold can, under certain conditions, be associated with a premature brittle interfacial solder joint fracture failure. This failure typically occurs at the interface of the nickel deposit and the intermetallic formed during soldering. The exposed nickel usually exhibits a “blackish” discolouration that has led to the term “black pad” being used to describe such failures. Although black pad usually occurs at very low levels, its incidence can be catastrophic and hence much work has been done by numerous workers to elucidate further the causes and mechanisms of this failure. This paper reviews the current understanding of the black pad failures and details work carried out by Shipley to extend this knowledge and to help users minimise the likelihood of its formation.

An electrochemical polarisation technique was employed to measure the porosity of electroless nickel (EN) coating. The technique is based on the change observed in the electrochemical parameters with varying cathode and/or anode area on a bimetallic corroding surface. The nickel coating test samples were obtained from a hypophosphite plating bath in the presence of different complexing agents. This technique was used to estimate the effect of coating thickness on porosity and the influence of addition of different complexing agents to EN baths on porosity. The results suggest that, unlike other conventional methods, the electrochemical, a non‐destructive method, can detect the smallest pore in an EN‐coating and quantify its size in terms of pore area fraction.