Structure and Electrochemical Characterization of Ni+W+Si Composite Coatings in an Alkaline Solution

Ni+W+Si composite coatings were prepared by nickel deposition from a bath containing suspension of tungsten and silicon powders. These coatings were obtained under galvanostatic conditions, at the current density of jdep. = 0.100 A cm-2 and at the temperature of 338 K. A scanning electron microscope was used for surface morphology characterization of the coatings. Chemical composition of the coatings was determined by EDS method and phase composition investigations were conducted by X-ray diffraction. Thermal treatment of obtained coatings was conducted in the air and nitrogen atmosphere. Electrochemical corrosion resistance investigations were carried out in the 5 M KOH, using potentiodynamic method. It was found that Ni+W+Si coatings after thermal treatment in the air are more corrosion resistant in alkaline solution than Ni+W+Si coatings after thermal treatment in the nitrogen atmosphere and as-deposited coatings. The main reason of this is presence of new phases, in particular NiWO4 and SiO2.

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Influence of Thermal Treatment on the Electrochemical Properties of Ni+W+Mo+Si Composite Coatings in an Alkaline Solution

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.228.305 ◽

2015 ◽

Vol 228 ◽

pp. 305-309

Author(s):

Magdalena Popczyk ◽

Bożena Łosiewicz ◽

Eugeniusz Łągiewka ◽

A. Budniok

Keyword(s):

Thermal Treatment ◽

Composite Coatings ◽

Electrochemical Corrosion ◽

Argon Atmosphere ◽

X Ray Diffraction ◽

Corrosion Resistant ◽

X Ray ◽

Electrochemical Corrosion Resistance ◽

Galvanostatic Conditions ◽

Xrd Method

The Ni+W+Mo+Si composite coatings were prepared by electrodeposition under the galvanostatic conditions (jdep= -100 mA cm-2) from the nickel bath containing powders of tungsten, molybdenum and silicon. Thermal treatment of the obtained coatings was conducted in argon atmosphere. Chemical composition of the coatings was determined by energy dispersive spectrocopy (EDS). Phase composition investigations were conducted by X-ray diffraction (XRD) method. Studies of electrochemical corrosion resistance were carried out in 5 M KOH solution. On the basis of these investigations it was found that Ni+W+Mo+Si thermally treated coating is more corrosion resistant than Ni+W+Mo+Si as-deposited coating.

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Influence of Thermal Treatment on the Electrochemical Properties of Ni+Mo Composite Coatings in an Alkaline Solution

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.228.231 ◽

2015 ◽

Vol 228 ◽

pp. 231-236 ◽

Cited By ~ 1

Author(s):

Magdalena Popczyk ◽

B. Łosiewicz ◽

Eugeniusz Łągiewka ◽

A. Budniok

Keyword(s):

Thermal Treatment ◽

Electrochemical Properties ◽

Composite Coatings ◽

Electrochemical Corrosion ◽

X Ray Diffraction ◽

Corrosion Resistant ◽

X Ray ◽

Electrochemical Corrosion Resistance ◽

Galvanostatic Conditions ◽

Xrd Method

The Ni+Mo composite coatings were prepared by electrodeposition under the galvanostatic conditions (jdep= -300 mA cm-2) from the nickel bath containing molybdenum powders of different granulation (3-7 μm, <150 μm, <100 nm). Thermal treatment of the obtained coatings was conducted in the argon atmosphere. The surface morphology of the coatings was studied using a scanning electron microscopy (SEM). Chemical composition of the electrodeposits was determined by X-ray fluorescence spectroscopy (XRF). Phase composition investigations were conducted by X-ray diffraction (XRD) method. Investigations of hydrogen evolution reaction (HER) and electrochemical corrosion resistance were carried out in 5 M KOH solution. It was found that for the Ni+Mo thermally treated coatings the decrease in activity towards the HER was observed. Simultaneously these coatings are more corrosion resistant than Ni+Mo as-deposited coatings. The reasons for the electrochemical properties of these coatings have been discussed.

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Electrodeposition and Thermal Treatment of Nickel Coatings Containing Cobalt

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.228.158 ◽

2015 ◽

Vol 228 ◽

pp. 158-162

Author(s):

Magdalena Popczyk ◽

B. Łosiewicz ◽

Eugeniusz Łągiewka ◽

A. Budniok

Keyword(s):

Thermal Treatment ◽

Absorption Spectrometry ◽

Amorphous Structure ◽

X Ray Diffraction ◽

Nickel Coatings ◽

Developed Surface ◽

Surface Development ◽

Multi Phase ◽

Morphology Characterization

The Ni-P and Ni-Co-P coatings were electrodeposited at the deposition current density ofjdep= -20 mA cm-2. Thermal treatment of these coatings was conducted in air at 400oC for 1 h. Scanning electron microscopy (SEM) was used for surface morphology characterization of the coatings. Phase composition was investigated by X-ray diffraction (XRD) method. Atomic absorption spectrometry (AAS) was applied to specify chemical composition of obtained coatings. It was found that introduction of Co into amorphous Ni matrix caused the surface development of the obtained deposit. The Ni-P coating revealed an amorphous structure. The Ni-Co-P coating was formed of the amorphous matrix and the amorphous alloy ingredient. Thermal treatment of the coatings allowed to obtain new multi-phase materials with slightly developed surface.

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Effect of Current Density on the Performance of Ni–P–ZrO2–CeO2 Composite Coatings Prepared by Jet-Electrodeposition

Coatings ◽

10.3390/coatings10070616 ◽

2020 ◽

Vol 10 (7) ◽

pp. 616

Author(s):

Zhaoyang Song ◽

Hongwen Zhang ◽

Xiuqing Fu ◽

Jinran Lin ◽

Moqi Shen ◽

...

Keyword(s):

Wear Resistance ◽

Corrosion Resistance ◽

Current Density ◽

Composite Coatings ◽

Electrochemical Corrosion ◽

Corrosion Current ◽

X Ray Diffraction ◽

X Ray ◽

Jet Electrodeposition ◽

Electrochemical Corrosion Resistance

The objective of this study was to improve the surface properties, hardness, wear resistance and electrochemical corrosion resistance of #45 steel. To this end, Ni–P–ZrO2–CeO2 composite coatings were prepared on the surface of #45 steel using the jet-electrodeposition technique by varying the current density from 20 to 60 A/dm2. The effect of current density on the performance of the composite coatings was evaluated. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) were applied to explore the surface topography, elemental composition, hardness and electrochemical corrosion resistance of the composite coatings. The results showed that with the increase in the current density, the hardness, wear resistance, and electrochemical corrosion resistance tends to increase first and then decrease. At a current density of 40 A/dm2, the hardness reached a maximum of 688.9 HV0.1, the corrosion current reached a minimum of 8.2501 × 10−5 A·cm−2, and the corrosion potential reached a maximum of −0.45957 V. At these values, the performance of the composite coatings was optimal.

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Preparation and Characterization of Zn-Containing Hydroxyapatite/TiO2 Composite Coatings on Ti Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.685.367 ◽

2011 ◽

Vol 685 ◽

pp. 367-370 ◽

Cited By ~ 3

Author(s):

Min Qi ◽

Da Yi Yang ◽

Jing Ying Zhang ◽

Hong Jun Ai

Keyword(s):

Adhesion Strength ◽

Composite Coatings ◽

Energy Dispersive Spectrometer ◽

Sol Gel ◽

X Ray Diffraction ◽

Zn Content ◽

Micro Arc Oxidation ◽

Gel Technique ◽

Bacteria Resistance

In order to improve the osteoblast growth and bacteria resistance, Zn-containing hydroxyapatite (Zn-HA) and titanium oxide (TiO2) composite coatings were prepared to improve binding between coating and Ti substrate. TiO2 film was prepared on the surface of Ti by micro-arc oxidation (MAO) and Zn-HA coating was deposited on TiO2 using sol–gel technique. Phase structure, composition and microstructure of the surface coatings were analyzed by X-ray diffraction (XRD) and Energy Dispersive Spectrometer (EDS), respectively. The adhesion strength between the coatings with different Zn content was measured by tensile testing. The results showed that there was no significant influence of Zn content on adhesion strength between coating and Ti substrate.

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Appraisal on corrosion performances of CrNi, TiAlN/CrNi and CrNi–Al2O3–TiO2 coatings on H13 hot work mold

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-09-2019-2175 ◽

2020 ◽

Vol 67 (2) ◽

pp. 150-157

Author(s):

Kong Dejun ◽

Li Jiahong

Keyword(s):

Corrosion Resistance ◽

Salt Spray ◽

Test Chamber ◽

Electrochemical Corrosion ◽

Optical Microscope ◽

Electrochemical Performances ◽

X Ray Diffraction ◽

H13 Steel ◽

Content Type ◽

Electrochemical Corrosion Resistance

Purpose The purpose of this paper is to evaluate the salt spray corrosion (SSC) and electrochemical corrosion performances of CrNi, TiAlN/NiCr and CrNi–Al2O3–TiO2 coatings on H13 steel, which improved the corrosion resistance of H13 hot work mold. Design/methodology/approach CrNi, TiAlN/NiCr and CrNi–Al2O3–TiO2 coatings were fabricated on H13 hot work mold steel using a laser cladding and cathodic arc ion plating. The SSC and electrochemical performances of obtained coatings were investigated using a corrosion test chamber and electrochemical workstation, respectively. The corrosion morphologies, microstructure and phases were analyzed using an electron scanning microscope, optical microscope and X-ray diffraction, respectively, and the mechanisms of corrosion resistance were also discussed. Findings The CrNi coating is penetrated by corrosion media, producing the oxide of Fe3O4 on the coating surface; and the TiAlN coating is corroded to enter into the CrNi coating, forming the oxides of TiO and NiO, the mechanism is pitting corrosion, whereas the CrNi–Al2O3–TiO2 coating is not penetrated, with no oxides, showing the highest SSC resistance among the three kinds of coatings. The corrosion potential of CrNi coating, TiAlN/CrNi and CrNi–Al2O3–TiO2 coatings was –0.444, –0.481 and –0.334 V, respectively, and the corresponding polarization resistances were 3,074, 2,425 and 86,648 cm2, respectively. The electrochemical corrosion resistance of CrNi–Al2O3–TiO2 coating is the highest, which is enhanced by the additions of Al2O3 and TiO2. Originality/value The CrNi, TiAlN/CrNi and CrNi–Al2O3–TiO2 coatings on H13 hot work mold were firstly evaluated by the SSC and electrochemical performances.

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Synthesis and Characterization of Pd/Ag/SiO2 Nano-Composite Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.726.204 ◽

2017 ◽

Vol 726 ◽

pp. 204-209 ◽

Cited By ~ 1

Author(s):

Jing Yang ◽

Bao Song Li ◽

Zhi Tong ◽

Rui Hua Mu

Keyword(s):

Zeta Potential ◽

Size Distribution ◽

Sol Gel ◽

Linear Structure ◽

Nitrogen Atmosphere ◽

Molar Ratio ◽

Powder Materials ◽

X Ray Diffraction ◽

Silica Network

Pd/Ag/SiO2 sols and powder materials were prepared by adding AgNO3 and Pd (NO3)2·2H2O into a methyl-modified silica sol. Tetraethylorthosilicate and methyltriethoxysilane were used as the silica precursor for the sol-gel reaction. The obtained SiO2 sols and powder materials were characterized by sol particle size distribution, zeta potential analysis, UV-Vis spectra, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) measurement. It was found that most of the particle sizes of the prepared Pd/Ag/SiO2 sols are about 2~10 nm with narrow size distribution. The zeta potential of Pd/Ag/SiO2 sol with Pd/Ag molar ratio of 7.5/2.5 presents the highest value. The FTIR analysis substantiates that the Si-CH3 groups exist in the silica network and the formed Pd/Ag/SiO2 sol particles possess linear structure. XRD characterization indicates that the Pd2+ and Ag+ in the Pd/Ag/SiO2 materials had be reduced to Pd0 and Ag0, respectively, after annealed in a nitrogen atmosphere at 350°C.

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Structure and Corrosion Resistance of Iron Coatings Containing Silicon Powders

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.1926 ◽

2011 ◽

Vol 399-401 ◽

pp. 1926-1931 ◽

Cited By ~ 1

Author(s):

Yi Wang ◽

Gang Chen ◽

Wei Dong Liu ◽

Qiong Yu Zhou ◽

Qing Dong Zhong

Keyword(s):

Corrosion Resistance ◽

Phase Composition ◽

Thermal Treatment ◽

Surface Morphology ◽

Electrochemical Impedance ◽

Electrochemical Corrosion ◽

Active Surface ◽

Active Surface Area ◽

Two Phase ◽

Electrochemical Corrosion Resistance

Fe + Si coatings were prepared by iron deposition from a bath containing a suspension of silicon powders. These coatings were obtained at galvanostatic conditions, at the current density of jdep=−0.020 A cm−2 and at the temperature of 338 K. For determination of the influence of phase composition and surface morphology of these coatings on changes in the corrosion resistance, these coatings were modified in an argon atmosphere by thermal treatment at 873 K for 2h. A scanning electron microscope was used for surface morphology characterization of the coatings. The chemical composition of the coatings was determined by EDS and phase composition investigations were conducted by X-ray diffraction. It was found that the as-deposited coatings consist of a two-phase structure, i.e., iron and silicon. The phase composition for the Fe + Si coatings after thermal treatment is markedly different. The main peaks corresponding to Fe and Si coexist with the new phases: FeSi. Electrochemical corrosion resistance investigations were carried out in 3.5wt% NaCl, using potentiodynamic and electrochemical impedance spectroscopy (EIS) methods. On the basis of these investigations it was found that the Fe + Si coatings after thermal treatment are more corrosion resistant in 3.5wt% NaCl solution than the as-deposited coatings. The reasons for this are a reduction in the amount of free iron and silicon, the presence of new phases (in particular silicides), and a decrease of the active surface area of the coatings after thermal treatment.

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Electrochemical Characterization of Nickel-Phosphorus Based Coatings Containing Cobalt

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.228.299 ◽

2015 ◽

Vol 228 ◽

pp. 299-304

Author(s):

Magdalena Popczyk ◽

B. Łosiewicz ◽

Eugeniusz Łągiewka ◽

A. Budniok

Keyword(s):

Electrode Materials ◽

Electrochemical Impedance ◽

Porous Electrode ◽

Absorption Spectrometry ◽

X Ray Diffraction ◽

Morphology Characterization ◽

Galvanostatic Conditions ◽

Matrix Powder ◽

Xrd Method

The Ni-P, Ni-Co-P and Ni-P+Co coatings were obtained in galvanostatic conditions at the current density ofjdep= -200 mA cm-2. A stereoscopic microscope was used for surface morphology characterization of the coatings. The X-ray diffraction (XRD) method was used to determine phase composition of the coatings and the atomic absorption spectrometry (AAS) was applied to specify their chemical composition. The behavior of the obtained coatings was investigated in the process of hydrogen evolution reaction (HER) from 5 M KOH using steady-state polarization and electrochemical impedance spectroscopy (EIS) methods. It was found that introduction into Ni-P amorphous matrix powder of cobalt produced porous electrode materials which could be used for the HER.

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