Nickel-phosphorus Coatings Research Articles

Enhancing corrosion resistance of Nd-Fe-B magnets with amorphization Ni-P coatings

Nd-Fe-B permanent magnets, due to the unique phase structure, demand exceptional corrosion resistance. Electrodeposited nickel-phosphorus (Ni-P) coatings are recognized for their superior anti-corrosion performance, but the performance of electrodeposited Ni-P coatings with different crystallinity varies considerably from process to process. In this study, we propose a strategy to grow Ni-P coatings that exhibit varying crystallographic orientations and degrees of crystallinity. Meanwhile, the differences in structure, morphology, corrosion resistance, and mechanical properties between crystalline and amorphous Ni-P coatings were systematically investigated. The results show that the crystalline Ni-P alloy coating predominantly forms on the Ni(111) crystal plane, with poor surface topographic flatness. In contrast, the amorphous Ni-P coating demonstrates better surface topographic flatness. The crystalline Ni-P alloy coating exhibits a corrosion potential of −0.63 V, a corrosion current density of 5.6 × 10−7 A cm−2, and a hardness of 583HV. In comparison, the completely amorphous Ni-P alloy coating shows an improved corrosion potential of −0.38 V, an exceedingly low corrosion current density of 9.5 × 10−10 A cm−2, and an increased hardness of 622HV.

Development of an environmentally friendly pre-treatment for electroless metallisation of glasses

ABSTRACT In recent years, the growing need for materials that have high thermal resistance, non-flammability, high radioactive resistance and durability is the reason for the development of new technologies for electroless metallisation of glasses. The most important operation is surface roughening, which is usually carried out in etching solutions containing HF acid, which is harmful to the environment and to health and safety at work. In this regard, the aim of the present research is the creation of an environmentally friendly technology for electroless metallisation of glasses. Тhe samples were pre-treated in two ways: one group was covered with a thin polymer film (Plastik 70 special glue or epoxy resin, thinned with dimethylformamide), and the other was degreased and treated with a solution of (3 aminopropyl) trimethoxysilane (APTS) at different concentrations and under different conditions. All samples were activated with a colloidal activator, after which copper or nickel-phosphorus coatings were deposited by electroless plating.

Influence of substituents in bis(2-amino-5-R-phenyl)disulfide on the deposition processes and properties of nickel-phosphorus coatings

Influence of substituents in bis(2-amino-5-R-phenyl)disulfide on the deposition processes and properties of nickel-phosphorus coatings

Advanced corrosion resistance and mechanistic insights of electroless Ni-P-PTFE coatings on L245NS substrate in H2S-saturated environments

The extraction and transportation of oil and gas pose significant challenges due to corrosive environments, particularly hydrogen sulfide (H2S) exposure. This study investigates the use of polytetrafluoroethylene (PTFE) to enhance the corrosion resistance of nickel‑phosphorus (NiP) coatings in H2S-rich environments. Electroless deposition was employed to prepare Ni-P/PTFE coatings, which were then subjected to simulated H2S corrosion tests. Results indicate that the incorporation of PTFE led to a more uniform NiP coating with reduced porosity, significantly improving corrosion resistance. The coatings exhibited enhanced protective performance by stabilizing corrosion product layers and preventing the formation of corrosion channels. Ni-P-PTFE coatings overcame the existing research challenge of NiP coatings' corrosion in H2S environments, showing no penetration of the corrosive medium into the substrate after 720 h of immersion. The corrosion rate of the coating is only 0.0261 mm/year, only 4.27 % of the corrosion rate of the L245NS substrate in the early stage of corrosion. Moreover, after characterization by SEM, XRD and XPS, it was found that the presence of PTFE altered the corrosion mechanism, promoting the formation of stable nickel sulfide and oxide layers on the surface. This study sheds light on the mechanisms underlying PTFE-enhanced corrosion resistance in NiP coatings, offering promising implications for extending the lifespan of equipment in the oil and gas industry.

Ni-B-PTFE Nanocomposite Co-Deposition on the Surface of 2A12 Aluminum Alloy.

The spinning cup, a crucial component of textile equipment, relies heavily on 2A12 aluminum alloy as its primary raw material. Commonly, electroplating and chemical nickel-phosphorus (Ni-P) plating are employed to improve the surface characteristics of the object. Nevertheless, due to the growing expectations for the performance of aluminum alloys, the hardness and wear resistance of Ni-P coatings are no longer sufficient to fulfill industry standards. This study primarily focuses on the synthesis of Ni-B-PTFE nanocomposite chemical plating and its effectiveness when applied to the surface of 2A12 aluminum alloy. We examine the impact of the composition of the plating solution, process parameters, and various other factors on the pace at which the coating is deposited, the hardness of the surface, and other indicators of the coating. The research findings indicate that the composite co-deposited coating achieves its optimal surface morphology when the following conditions are met: a nickel chloride concentration of 30 g/L, an ethylenediamine concentration of 70 mL, a sodium borohydride concentration of 0.6 g/L, a sodium hydroxide concentration of 90 g/L, a lead nitrate concentration of 30 mL, a pH value of 12, a temperature of 90 °C, and a PTFE concentration of 10 mL/L. The coating exhibits consistency, density, a smooth surface, and an absence of noticeable pores or fissures. The composite co-deposited coating exhibits a surface hardness of 1109 HV0.1, which significantly surpasses the substrate's hardness of 232.38 HV0.1. The Ni-B-PTFE composite coating exhibits an average friction coefficient of around 0.12. It has a scratch width of 855.18 μm and a wear mass of 0.05 mg. This coating demonstrates superior wear resistance when compared to Ni-B coatings. The Ni-B-PTFE composite coating specimen exhibits a self-corrosion potential of -6.195 V and a corrosion current density of 7.81 × 10-7 A/cm2, which is the lowest recorded. This enhances its corrosion resistance compared to Ni-B coatings.

Wear Resistance Behavior of Low-, Mid-, and High-Phosphorus Electroless Ni-P Coatings Heat-Treated in the Air Environment

The high-temperature heat treatment of electroless nickel–phosphorus (Ni-P) coatings in an air environment, and its consequences have scarcely been investigated. This work investigated tribological characteristics of the high-temperature, heat-treated, electroless Ni-P coatings on steel substrates with low-, mid-, and high-phosphorus content for which the average phosphorus content was 2.4 wt.%, 7.1 wt.%, and 10.3 wt.%, respectively. X-ray fluorescence and energy dispersive spectroscopy were implemented to determine the phosphorus content of the coatings. The oxidation of Ni and the formation of the NiO layer on the coating surface was confirmed by the X-ray diffraction technique. A reciprocating sliding method on a ball-on-flat system was utilized to evaluate the coating’s friction and wear behavior. Among the coatings with varying phosphorus content, a high hardness of 1086 HV was found for high-phosphorus coating when heat-treated at 400 °C in an air environment, and that was decreased to 691 HV when heat-treated at 650 °C. The oxidation of nickel in the electroless Ni-P coating occurred when heat-treated at 400 °C in an air environment, and this phenomenon was increased more when the temperature was increased to 650 °C. The characteristics of the NiO layer that formed on the surface of the heat-treated electroless Ni-P coating were influenced by the concentration of phosphorus, which caused different colors of NiO to be seen on the Ni-P coating surface. A greenish black NiO layer on the low-phosphorus and black NiO layer on the mid- and high-phosphorus Ni-P coating was developed during heat treatment at 650 °C in an air atmosphere. The adhesion and tribological characteristics of the Ni-P coatings were affected by the NiO layer developed on the heat-treated Ni-P coating surfaces. The Ni-P coatings with mid- and high-phosphorus content showed enhanced wear-resistance characteristics when they underwent heat treatment in an air atmosphere at the high temperature of 650 °C. The wear volume obtained for as-plated mid-phosphorus and high-phosphorus Ni-P coatings was 0.111 mm3 and 0.128 mm3, respectively, and that was reduced to 0.031 mm3 and 0.051 mm3, respectively, after the high-temperature heat treatment.

Electrochemical and Thermodynamic Investigation of Drug Solfarlem as a Potential Corrosion Inhibitor for Nickel-Phosphorus Coatings

Electrochemical and Thermodynamic Investigation of Drug Solfarlem as a Potential Corrosion Inhibitor for Nickel-Phosphorus Coatings

Wear behavior of graded nickel-phosphorus coatings with a medium phosphorus top layer: An experimental and molecular dynamics simulation study

Nickel-phosphorus electroless plating is widely used to improve surface properties. Despite various applications in industry, mismatch properties at the interface between the Nickel-Phosphorus layer and the substrate can cause stress concentration that could fail of the interface and consequently reduce the wear resistance of the deposit. Recent studies confirmed that the graded Nickel-Phosphorus electroless plating coatings could be considered an effective approach to reducing the stress at the interface. Therefore, in this study, the graded nickel-phosphorus coatings with various phosphorus content in the form of multilayer structures were investigated. The phosphorus content in the nickel-low phosphorus layer (Ni-LP), nickel-medium phosphorus layer (Ni-MP), and nickel-high phosphorus layer (Ni-HP) were 4.88 wt%, 8.99 wt%, and 13.88 wt%, respectively. In the Ni-LP/Ni-MP double layer, the wear resistance was 1.5 times compared to the Ni-MP single layer. Using the molecular dynamics simulation, it is shown that during the wear process, the inhibition of propagation of cracks has occurred for graded structure. The experimental results showed that the higher hardness of the Ni-MP upper layer, compact surface morphology, and the crystallinty graded structure were important parameters in improving the wear resistance of the Ni-LP/Ni-MP coating. The direct relationship between the experimental parameters and the wear simulated results of the Ni-LP/Ni-MP coating also confirmed each other completely.

Zincate Replacement, an Economical a Sustainable Alternative for the Metal-Coating of Aluminum

Aluminum parts are of great value for many industries as they are cost-effective, very lightweight combined with a good mechanical strength. However, when parts are exposed to corrosive and abrasive conditions it is preferred to protect them with anodizing, powder coating, or for technical critical applications with nickel-phosphorus (NiP) coatings. Most preferred for functional parts such as scroll compressors, connectors,... is electroless NiP (EN) as it is has a low thickness variation in the final deposit and does not need the application of current like galvanic NiP coatings.Depositing an adherent layer of electroless NiP onto aluminum needs an alloy-specific pre-treatment. The largest challenge in pre-treatment lies in the very fast formation of Al2O3 oxide under neutral pH conditions of 4 - 9. For decades a very effective way to inhibit the re-oxidation of aluminum is the use of alkaline zinc as interim coatings that dissolve in the electroless NiP electrolyte before NiP deposition starts. Commercial solutions are optimized to produce an as thin and homogenous as possible zinc deposit to minimize the drag-in of zinc into the NiP electrolyte. At levels of 80 - 200 mg/l zinc starts to lower the adhesion and plating rate of deposited EN coatings. As results the nickel process needs to be discarded before nickel deposition capacity of electrolyte is fully reached (~ 40 g/l plated Ni). The impact of Zn contamination is most critical as lower the thickness of the EN layer is. At very thin thicknesses below 4 µm the increase of zinc is very large, and electrolytes need to be discarded at 6-12 g/l plated nickel creating higher chemical waste, maintenance effort, and cost. Due to technical changes in many applications, different and more parts will be composed of aluminum. In contrast to established applications NiP that exhibit EN layers > 5 µm new applications arise with the upcoming EV and Battery market that request thinner NiP layers. The most extreme case is reel-to-reel plating of thin (< 50 µm) foils with NiP deposits below 4 µm.In the present work, the application of a new chemical concept of aluminum pre-treatment for low-thickness EN coatings will be presented that reduces the number of needed process steps compared to double zincate by at least 2 steps (excl. rinses) without the need for special equipment such as pulse plating and others. Differences in the initiation of electroless NiP deposition and the correlated adhesion will be evaluated. As a model case, the application of thin NiP layers (< 4 µm) on pure Aluminum foils will be shown and discussed. Figure 1

Effect of modifiers on the structure formation and properties of nickel-phosphorus coatings applied to powder steels

The paper shows the effect of solution temperature on the deposition rate of applying composite nickel-phosphorus coatings modified with boron nitride and polytetrafluoroethylene to powder samples made of improved P40, P40Kh and P40KhN steels obtained by hot stamping of porous sintered blanks. It has been experimentally established that within the range of 70–90 °C, the average deposition rate of modified BN and (C2F4)n coatings is 15–19 μm/h, while the chemical composition of the improved steels and the surface configuration of the samples have no effect on the coating build-up rate. The mechanism of the formation of the structure and properties of nickel-phosphorus coatings (NiPC) without additives and those of NiPC modified with boron nitride and polytetrafluoroethylene during deposition, sintering and running-in is revealed. It has been established that immediately after deposition, Ni–P coating has an amorphous structure with inclusions of nickel particles, and its microhardness does not exceed 380–390 MPa with no modifiers added. In the dry friction mode at the running-in stage, Ni12P5 and Ni2P phases are formed in the modified Ni–P coatings, allowing to improve their tribological properties, and in the steady-state mode, the phase disordering of the modified NiPC proceeds. It has been experimentally revealed that the coefficient of friction and wear decrease by 1.3 times when only (C2F4)n is introduced into Ni–P coating, these indices decrease by 1.6 times when only BN is added, and they decrease almost twice when BN and (C2F4)n are introduced together. It has been established that upon the combined (complex) modification of NiPC with BN and (C2F4)n after the heat treatment, there is almost no nickel oxide phase, nickel boride of NiB type is formed in the coating during running-in, and its content does not decrease when entering the stationary friction mode, thus increasing tribotechnical properties of the coating. During running-in, the coefficient of friction of Ni–P + BN + (C2F4)n coating decreases from 0.28 to 0.19, and the wear rate of such a coating in the stationary friction mode is 1.5 mg/h. The efficiency of applying the antifriction nickel-phosphorus coatings modified with BN + (C2F4)n to the products made of the improved structural steels obtained by various methods has been theoretically and experimentally substantiated.

STUDY OF METHODS OF INCOMING INSPECTION OF METAL COATINGS OF SHUT-OFF VALVES OF PIPELINES

The article describes methods and tools for inspection of thickness and hardness of coatings of elements of ball shut-off valves (ball plugs), which are one of the main elements of main pipelines and distribution networks. Properties of nickel-phosphorus (ENP) coatings most frequently used to protect ball plugs from corrosion and abrasion are analyzed. Various methods and means of control are considered. In the process of experimental studies, the thickness of coatings was measured by magnetic induction and eddy current methods of nondestructive control, as well as by ball abrasion method. Hardness values were measured by microvickers and ultrasonic contact impedance methods. The main sources of measurement errors were identified. Conclusions are drawn for each of the methods used in the incoming inspection of coatings.

Technological Support of Wear Resistance in the Repair of Pistons Made of Aluminum Alloys with Nickel–Phosphorus Coating

Technological Support of Wear Resistance in the Repair of Pistons Made of Aluminum Alloys with Nickel–Phosphorus Coating

Influence of silicon carbides on the structure and properties of composite nickel-phosphorus coating

The authors studied the structure, properties and corrosion resistance in various acids of nickel-phosphorus coatings with dispersed silicon carbides after crystallization annealing under various modes. Temperatures of the beginning of crystallization after heating at speeds of 1, 5, 20 °С/min and the percentage of crystalline phases formed under isothermal conditions (nickel phosphide Ni3P and nickel) were determined. High microhardness of more than 1000 HV is achieved in a composite nickel-phosphorus coating with dispersed particles of silicon carbides during prolonged low-tempera­ture annealing, accompanied by crystallization with formation of already insignificant (10 %) amounts of Ni3P. The revealed dispersed Ni3P located both in the body and along boundaries of the grain, make the main contribution to the increment of microhardness. The yield strength and ultimate strength of coatings increase during crystallization annealing by only 12 – 15 MPa, and the elongation drops to zero, which is due to the formation of brittle Ni3P compounds. Annealing with short soaking at crystallization temperatures leads to the fact that silicon carbides exhibit a barrier effect, reducing the intensity of formation of crystalline Ni3P and corrosion resistance, while long soaking at lower crystallization temperatures forms about 70 % Ni3P, contributing to consistently high hardness and improved corrosion resistance. Corrosion resistance of composite coatings Ni-P + silicon carbides, regardless of the heat treatment modes, is maximum in acetic and orthophosphoric acids at 70 % nickel phosphide and minimum in nitric acid and its mixtures with other acids.

Corrosion resistance of composite NI-P coatings in various aggressive media

The paper studies corrosion resistance in highly aggressive media of composite nickel-phosphorus coatings after isothermal annealing at different temperatures accompanied by crystallization. The phase composition of chemically deposited Ni-P coating containing about 1% dispersed SiC was analyzed. Gravimetric method was used to determine the mass loss of the samples as a result of daily exposure to various acids and in a solution of nitric acid with a concentration from 5 to 65%, which is extremely aggressive for Ni-P coatings. At each heat treatment, the steel witness samples were used to determine the microhardness by the Vickers method at a load of 100 g. The dependence of the parameters of the corrosion process on the presence of a dispersed additive and the phase composition of the coating has been established. At low holding times the dispersed phase exhibits a barrier effect reducing crystalline phosphide Ni3P formation during annealing and corrosion resistance; meanwhile, prolonged holding at lower temperatures produces about 70% Ni3P, stable high hardness values and improved corrosion resistance values. Lowering the coating heat treatment temperature in an oxidizing environment reduces the intensity of phosphorus burn-off from the surface and decreases all coating properties. The concentration of nitric acid in the solution at the level of 5-15% is critical and contributes to the dissolution of all coatings, regardless of their composition.The conducted research and revealed regularities made it possible to determine the contribution of the phase composition and presence of the dispersed additive to the formation of the main service characteristics of the nickel-phosphorus coatings - microhardness and resistance to aggressive media, as well as to determine the technological modes of heat treatment that allow the formation of optimum properties of products used in the oil and gas industry.

Electroless Nickel Phosphorus Coatings to Mitigate the Corrosion of Construction Steel

Reinforced concrete is widely used in structures and construction, but its durability is limited due to corrosion of the embedded steel rebars. Thus, mitigation of corrosion of construction steel rebars is an important area of research. The present work reports the ability of electroless nickel phosphorus coating for corrosion protection of Fe-600-grade steel rebars used for construction purposes in chloride and sulphate environment. The coating deposited on Fe-600 rebar was Ni-P and was subjected to electrochemical tests in 3.5% NaCl and 0.5M H2SO4. Severe corrosion pitting and cracking were observed for the uncoated rebar while Ni-P coating showed nobler corrosion potential and low corrosion current density in the corrosive environments.

Chemical black nickel coatings on steels

Having high corrosion resistance and hardness, black conversion coatings are used as functional, as well as protective and decorative coatings. Black chrome and nickel electroplated coatings are mainly used for these purposes. The main drawbacks of the chromium plating processes are related to the fact that they are rather difficult to realize and control and that they consume a great amount of energy as the solutions need to be heated up and some of the heat gets lost during hydrogen evolution reaction. The known black nickel plating processes are less energy intensive and easier to implement, however they have their drawbacks, such as low protective ability and wear resistance and poor adhesion to the substrate, especially to steel. This paper describes certain processes that were tested, as well as two plating techniques for producing black wear-resistant coatings with a high protective ability on chemically deposited nickel-phosphorus layers. It was found that the treatment of black coatings with nitric acid and anodic treatment with phosphoric acid lead to increased roughness and porosity of the coatings. Nickel oxides NiO, Ni2O3, as well as nickel phosphates were found in the final coating. It was established that heat treatment enhances the wear resistance and protective ability of black nickel-phosphorus coatings and they even outperform black chrome and nickel electroplated coatings. The properties of the resulting coatings were studied using an OLYMPUS LEXT4100 confocal laser microscope, a Taber Elcometer 5135 rotary abraser, an EDX-7000 energy-dispersive spectrometer, an HB100 Auger microscope (Vacuum Generators, GB), and a 410 Quick Start Guide reflectometer. The paper demonstrates the possibility of using a safer chemical nickel plating process instead of chromium and nickel electroplating processes.The authors would like to thank the Mendeleev Shared Knowledge Centre for&nbsp;support of this research.

Impact of Die Coatings on Forming Conditions in Electromagnetic Embossing of Thin Sheet Metal

In electromagnetic embossing, the interaction of the magnetic field and the induced current density results in body forces that enable the replication of optical microstructures into thin sheet metals. However, as the sheet metal is completely penetrated by the magnetic field, electromagnetic properties of the dies need to be considered in process design, as they influence the forming conditions by changing the field distribution, force vectors and eddy current densities. With die coatings like electroless nickel–phosphorus (NiP), the electromagnetic properties of the die change. Therefore, the effect of both - die substrate and coating material - was studied to find advantageous conditions for electromagnetic embossing. Within two-dimensional electromagnetic field simulation, the electromagnetic properties of coating and substrate material were varied in addition to the coating thickness. To validate the results, electromagnetic embossing experiments were carried out. Here, different dies were fabricated from aluminum (uncoated) and cold work steel with 200 µm and 400 µm thick electroless nickel–phosphorus coatings that were subsequently micro-structured in optical surface quality. It was demonstrated by numerical and experimental results that the coating and the substrate influence the electromagnetic embossing significantly in correspondence to their shielding behavior and field interaction due to electromagnetic properties and coating thickness.

Microstructure, composition and formation mechanism of ultra-black surfaces on the electrodeposited nickel-phosphorous coatings

Light absorbing materials are of practical importance in the production of optical devices in aerospace technology. A new method of light absorbing coatings preparation on the basis of electrodeposited nickel-phosphorus coatings has been proposed. Modification of the electrolyte for nickel-phosphorus plating by the addition of saccharine allowed preparing an ultrablack surface with a reflectance coefficient less than 0.5%. Chemical composition of both surfaces has been studied using X-ray photoelectron spectroscopy. The mechanism of their formation has been proposed. It has been found that etching in nitric acid leads to the partial oxidation of both surfaces with the formation of needle like microstructure.It also results in surface enrichment with phosphorus and formation of nickel phosphides particles of the variable composition. Products of the coating oxidation represent the matrix of amorphous nickel polyphosphates and polyphosphoric acids where fine Ni-P particles are distributed. Such composite structure is a well light absorbing medium. Formation of hypophosphite protective layer on the Ni–P coating obtained from saccharin free electrolyte reduces the thickness of light absorbing layer and changes its composition. Thus light absorbance ability of the coatings can be caused by both distribution of fine nickel-phosphorus particles in dielectric matrix and specific microstructure of their surfaces.

Structure, properties and quality of a composite nickel-phosphorus coating deposited on steel substrates of various compositions

Possible causes of defects during deposition and subsequent heat treatment (HT) of nickelphosphorus (Ni &ndash; P) coatings containing dispersed silicon carbides SiC on steel sheets with a thickness of 65&ndash;180 mm are investigated. The phase composition, microstructure, and microhardness of 40&ndash;70 &mu;m thick coatings chemically deposited on workpieces made of low- and medium-carbon low-alloy steels in various structural states and subjected to crystallization annealing of various durations were studied. According to X-ray diffraction studies, after deposition coatings are in an amorphous state and have low hardness and plasticity. Heat treatment in the temperature range of 400&ndash;450 &ordm;C is accompanied by an increase in coating adhesion, microhardness to the required values (1000 HV) according to specifications, and a drop in elongation to zero. This is due to the crystallization with the formation of carbides SiC and Si5C3, nickel with a face-centered cubic (fcc) lattice, and nickel phosphide Ni3P. The conducted studies and the revealed regularities made it possible to choose 09G2S thick steel sheet for some articles of oil and gas equipment, to establish the technological parameters for deposition of composite Ni&ndash;P coatings and the final HT modes that do not lead to the appearance of defects in the form of surface cracks, micropores and other discontinuities. The more homogeneous and stable the substrate structure, the less defects will appear in the coating. Another reason for rejection may be due to the transition from a less dense amorphous initial state to a denser crystalline state upon heating, accompanied by a reduction in volume in combination with a drop in the relative elongation of the coating to zero.

Effect of electrodeposition temperature on texture, strain, grain boundary constitution and corrosion behavior of Ni-P coatings with low phosphorous content

Nickel-phosphorus (Ni-P) alloy coatings were electrodeposited over mild steel substrate from a constant current DC power source. Effect of deposition bath temperature (15 ˚C, 20 ˚C, 25 ˚C, 35 ˚C) on the coating corrosion behavior in 3.5 wt.% NaCl solution was investigated. Corrosion analysis was conducted using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The 15 ˚C coating showed lowest polarization resistance (Rp = 2818.52 Ω.cm2) value indicating degraded corrosion resistance, whereas the 25 ˚C coating showed highest polarization resistance (Rp = 6992.285 Ω.cm2) value implying highest corrosion resistance performance amongst all coatings. This was also confirmed by the potentiodynamic polarization measurement where the 15 °C coatings and 25 °C coating showed respectively the highest and lowest corrosion current density (Icorr) values. Icorr values of 15 °C and 25 °C coating was 7.79 μA.cm−2 and 1.534 μA.cm−2, respectively. Analysis of the coating texture, strain and grain boundary constitution by the electron back scatter diffraction (EBSD) technique showed that the predominance of (101) high energy texture, lower fraction of low angle grain boundaries (LAGBs), and higher coating strain yielded high vulnerability to the corrosive attack for 15 ˚C coating, while (001) low energy growth texture with a relatively higher fraction of LAGBs and lower coating strain led to improved corrosion resistance in 25 °C coating.