Corrosion Behavior of Chromium Coated Zy-4 Cladding under CANDU Primary Circuit Conditions

The manuscript is focused on corrosion behavior of a Cr coating under CANada Deuterium Uranium(CANDU) primary circuit conditions. The Cr coating is obtained via the thermionic vacuum arc procedure on Zircaloy -4 cladding. The surface coating characterization was performed using metallographic analysis and scanning electron microscopy (SEM) with an energy dispersive spectra detector (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) investigations. The thickness of the Cr coating determined from SEM images is around 500 nm layers After the autoclaving period, the thickness of the samples increased in time slowly. The kinetic of oxidation established a logarithmic oxidation law. The corrosion tests for various autoclaving periods of time include electrochemical impedance spectroscopy (EIS) and potentiodynamic tests, permitting computing porosity and efficiency of protection. All surface investigations sustain electrochemical results and promote the Cr coating on Zircaloy-4 alloy autoclaved for 3024 h as the best corrosion resistance based on decrease in corrosion current density values simultaneously with the increase of the time spent in autoclave. A slow increase of Vickers micro hardness was observed as a function of the autoclaved period as well. The value reached for 3024 h being 219 Kgf/mm2 compared with 210 Kgf/mm2 value before autoclaving.

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Role of Mn addition on the general corrosion and pitting corrosion behavior of 13Cr stainless steel

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-10-2021-2555 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Jun He ◽

Lin Chen ◽

Yanjing Su

Keyword(s):

Stainless Steel ◽

Corrosion Behavior ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Alkaline Solutions ◽

General Corrosion ◽

Content Type ◽

X Ray ◽

Product Film

Purpose The purpose of this study is to elucidate the effect of Mn addition on the corrosion behavior of stainless steel. Design/methodology/approach Chronoamperometry, quasi-steady-state polarization and electrochemical impedance spectroscopy were used to investigate the corrosion behavior of Mn added A13Cr-HS sample and original S13Cr samples. In addition, the corrosion product film was characterized by a field emission scanning electron microscope equipped with energy-dispersive spectroscopy and X-ray photoelectron spectroscopy. Findings The A13Cr-HS sample with 8 wt.% Mn addition maintained good general corrosion resistance in both acidic and alkaline solutions compared to the original S13Cr sample. Additionally, the A13Cr-HS sample had good pitting resistance in an alkaline solution containing Cl−, but a weaker resistance in an acidic solution. Originality/value The influence of Mn addition on the formation mechanism of the passive film was systematically analyzed.

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Study of corrosion behavior of virgin and recycled Pb anodes used in zinc electrowinning industry

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-04-2017-1787 ◽

2020 ◽

Vol 67 (6) ◽

pp. 529-536

Author(s):

Shima Nakisa ◽

Naghi Parvini Ahmadi ◽

Javad Moghaddam ◽

Habib Ashassi-Sorkhabi

Keyword(s):

Corrosion Behavior ◽

Photoelectron Spectroscopy ◽

Surface Composition ◽

Electrochemical Impedance ◽

Zinc Electrowinning ◽

Composition Analysis ◽

Corrosion Properties ◽

Content Type ◽

X Ray ◽

Galvanostatic Polarization

Purpose The composition and corrosion behaviors of recycled and virgin Pb anode were investigated in industrial zinc electrowinning solution with different methods. The purpose of this study is the illustration of good anticorrosion activity of virgin Pb anodes compared to recycled one in industrial operation, while the compositions of both of them are the same which obtained from quantmetry method. Design/methodology/approach Its corrosion properties and electrocatalytic activity toward oxygen evolution reaction were appraised using potentiodynamic polarization, electrochemical impedance spectroscopy, galvanostatic polarization and ionic equilibrium methods. In addition, composition of anodes investigated with X-ray photoelectron spectroscopy (XPS) method. The surface composition of samples was studied via X-ray diffractogram (XRD). Findings The results indicate that the anodes display different anodic behaviors during the galvanostatic polarization. Virgin Pb anode shows a “potential reduction” about 320 mV lower than recycled Pb anode after 6 h of polarization; also, the stable potential after 72 h for virgin Pb anode is 100 mV lower than recycled Pb anode. Also, The XPS results show a trace amount of Cl in recycled anodes which cause the more corrosion activity. XRD results indicate that virgin Pb anodes have been covered by more oxides than recycled anodes after 72 h of electrowinning. Originality/value The treatment of corrosion behavior by virginity has not been detected by any researchers yet. Therefore, it is imperative to study the corrosion behavior and exact composition analysis of virgin and recycled Pb anodes to comprehension of them. This paper fulfills this need.

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Corrosion Resistance of TiN Coatings Prepared by Filtered Cathodic Vacuum Arc Process

MRS Proceedings ◽

10.1557/proc-0885-a09-07 ◽

2005 ◽

Vol 885 ◽

Cited By ~ 1

Author(s):

Jin-Bao Wu ◽

Yin-Wen Tsai ◽

Chin-Te Shih ◽

Mei-Yi Li ◽

Ming-Sheng Leu ◽

...

Keyword(s):

Stainless Steel ◽

Corrosion Behavior ◽

Photoelectron Spectroscopy ◽

Corrosion Current ◽

Vacuum Arc ◽

Tin Films ◽

X Ray ◽

Tin Coatings ◽

Filtered Cathodic Vacuum Arc ◽

Ti Mesh

ABSTRACTFor the purpose of developing the corrosion-resistant and low-cost metallic bipolar plates for direct methanol fuel cell (DMFC), Ti mesh, stainless steel and Si(100) were coated with TiN by using the filtered cathodic vacuum arc system (FCVA). These TiN films have received considerable attention because of its high anti-corrosion behavior and low contact-resistance. In order to improve the corrosion protective ability of TiN films and decrease pinholes of coating, growth modifications such as thickness of the coatings and bias applied to substrates have also been carried out. The microstructures and composition of TiN film were identified by the instrumental analyses such as scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The corrosion behavior of TiN coatings was studied in 0.5 M H2SO4 solutions by using potentiodynamic polarization method. The DC bias of −150 V was applied to the substrates to achieve a dense structure of approximately 400 nm coating of TiN, so that good corrosion protection of the Ti mesh and stainless steel substrates can be achieved. The TiN coating on stainless steel exhibited excellent corrosion behavior especially in lower corrosion current than 2×10−7 A/cm2.

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Effect of Zn Content on Structure, Roughness and Corrosion Behavior of Zn-Ni Alloys

Scientific Bulletin of Valahia University - Materials and Mechanics ◽

10.2478/bsmm-2019-0013 ◽

2019 ◽

Vol 17 (17) ◽

pp. 17-22

Author(s):

Hayette Faid

Keyword(s):

Corrosion Behavior ◽

Electrochemical Impedance ◽

Stripping Voltammetry ◽

X Ray Diffraction ◽

X Ray ◽

Ni Alloys ◽

Sulfate Bath ◽

Zn Content ◽

Polarization Test ◽

Δ Phase

AbstractIn this work, Zn-Ni alloys have been deposited on steel from sulfate bath, by electrodeposition method. The effect of Zn content on deposits properties was studied by cyclic voltammetry (CV), chronoaperometry (CA), linear stripping voltammetry (ALSV) and diffraction (XRD) and scanning electronic microscopy (SEM). The corrosion behavior in 3.5 wt. NaCl solution was examined using anodic polarization test and electrochemical impedance spectroscopy. X-ray diffraction of show that Zn-Ni alloys structure is composed of δ phase and γ phase, which increase with the decrease of Zn content in deposits. Results show that deposits obtained from bath less Zn2+ concentration exhibited better corrosion resistance.

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Ternary Composite of Molybdenum Disulfide-Graphene Oxide-Polyaniline for Supercapacitor

Journal of The Electrochemical Society ◽

10.1149/1945-7111/ac3f1e ◽

2021 ◽

Author(s):

Ke Qu ◽

Yuqi Bai ◽

Miao Deng

Keyword(s):

Graphene Oxide ◽

Molybdenum Disulfide ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Light Emitting Diode ◽

Rate Capability ◽

Energy Storage And Conversion ◽

Carbon Paper ◽

Power Sources ◽

X Ray

Abstract The ever-increasing need for small and lightweight power sources for use in portable or wearable electronic devices has spurred the development of supercapacitors as a promising energy storage and conversion system. In this work, a simple, facile and easy-to-practice method has been developed to employ carbon paper (CP) as the support to coat molybdenum disulfide (MoS2) and graphene oxide (GO), followed by electrodeposition of polyaniline (PANI) to render CP/MoS2-GO-PANI. The preparation parameters, such as amounts of MoS2, GO and number of aniline electropolymerization cycles, have been optimized to render CP/MoS2-GO-PANI the best capacitive performance. The as-prepared optimal CP/MoS2-GO-PANI is characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy. The supercapacitive properties of CP/MoS2-GO-PANI as an electrode have been evaluated electrochemically via cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy testing. CP/MoS2-GO-PANI delivers a specific capacitance of 255.1 F/g at 1.0 A/g and exhibits excellent rate capability under larger current densities. Moreover, a symmetrical supercapacitor is assembled and three are connected in series to power a light-emitting diode for ~15 minutes, demonstrating the promising application potential of CP/MoS2-GO-PANI-based supercapacitor.

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Corrosion behavior of a new 25Cr-3Ni-7Mn-0.66 N duplex stainless steel in artificial seawater

Materials Testing ◽

10.1515/mt-2020-0086 ◽

2021 ◽

Vol 63 (6) ◽

pp. 505-511

Author(s):

Songkran Vongsilathai ◽

Anchaleeporn Waritswat Lothongkum ◽

Gobboon Lothongkum

Keyword(s):

Stainless Steel ◽

Duplex Stainless Steel ◽

Passive Film ◽

Corrosion Behavior ◽

Electrochemical Impedance ◽

Melting Furnace ◽

Artificial Seawater ◽

Vacuum Arc ◽

Significant Difference ◽

Type Semiconductor

Abstract A new duplex 25Cr-3Ni-7Mn-0.66 N alloy was prepared in a vacuum arc re-melting furnace and characterized by metallographic and EPMA methods. Its corrosion behavior was investigated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and a Mott-Schottky (M-S) analysis in artificial seawater at room temperature and compared with those of super and normal commercial duplex stainless steel (SDSS and DSS). No significant difference in the open circuit potentials and pitting potentials was observed. Its passive film current density lies between those of SDSS and DSS. This was confirmed by EIS analysis. A pit attack was observed on the δ-phase for all duplex samples, because the PREN16 of the δ-phase was lower than that of the γ-phase. From the Mott-Schottky analysis, the passive films were found to be composed of bi-layer structures, a p-type semiconductor inner layer, and a n-type semiconductor outer layer. The degree of defect as well as the effect of nitrogen in passive film layer are discussed with respect to the point defect model.

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Organosilane-functionalization of nanostructured indium tin oxide films

Interface Focus ◽

10.1098/rsfs.2016.0056 ◽

2016 ◽

Vol 6 (6) ◽

pp. 20160056 ◽

Cited By ~ 10

Author(s):

R. Pruna ◽

F. Palacio ◽

M. Martínez ◽

O. Blázquez ◽

S. Hernández ◽

...

Keyword(s):

Surface Area ◽

Indium Tin Oxide ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Annealing Treatment ◽

Electrochemical Analysis ◽

Cyclic Voltammograms ◽

X Ray ◽

Chip Technology ◽

Significant Difference

Fabrication and organosilane-functionalization and characterization of nanostructured ITO electrodes are reported. Nanostructured ITO electrodes were obtained by electron beam evaporation, and a subsequent annealing treatment was selectively performed to modify their crystalline state. An increase in geometrical surface area in comparison with thin-film electrodes area was observed by atomic force microscopy, implying higher electroactive surface area for nanostructured ITO electrodes and thus higher detection levels. To investigate the increase in detectability, chemical organosilane-functionalization of nanostructured ITO electrodes was performed. The formation of 3-glycidoxypropyltrimethoxysilane (GOPTS) layers was detected by X-ray photoelectron spectroscopy. As an indirect method to confirm the presence of organosilane molecules on the ITO substrates, cyclic voltammetry and electrochemical impedance spectroscopy (EIS) were also carried out. Cyclic voltammograms of functionalized ITO electrodes presented lower reduction-oxidation peak currents compared with non-functionalized ITO electrodes. These results demonstrate the presence of the epoxysilane coating on the ITO surface. EIS showed that organosilane-functionalized electrodes present higher polarization resistance, acting as an electronic barrier for the electron transfer between the conductive solution and the ITO electrode. The results of these electrochemical measurements, together with the significant difference in the X-ray spectra between bare ITO and organosilane-functionalized ITO substrates, may point to a new exploitable oxide-based nanostructured material for biosensing applications. As a first step towards sensing, rapid functionalization of such substrates and their application to electrochemical analysis is tested in this work. Interestingly, oxide-based materials are highly integrable with the silicon chip technology, which would permit the easy adaptation of such sensors into lab-on-a-chip configurations, providing benefits such as reduced size and weight to facilitate on-chip integration, and leading to low-cost mass production of microanalysis systems.

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Rhombohedral Boron Nitride Epitaxy on ZrB2

10.26434/chemrxiv.12859805.v1 ◽

2020 ◽

Author(s):

Laurent Souqui ◽

Justinas Palisaitis ◽

Naureen Ghafoor ◽

Henrik Pedersen ◽

Hans Högberg

Keyword(s):

Electron Microscopy ◽

Boron Nitride ◽

Photoelectron Spectroscopy ◽

Amorphous Material ◽

Limited Area ◽

Sem Images ◽

Plan View ◽

Minute Amount ◽

X Ray ◽

Rhombohedral Boron

<div>Epitaxial rhombohedral boron nitride films were deposited on ZrB<sub>2</sub>(0001)/4H-SiC(0001) by chemical vapor deposition at 1485 °C from the reaction of triethylboron and ammonia and with a minute amount of silane (SiH<sub>4</sub>). X-ray diffraction (XRD) φ-scans yield the epitaxial relationships of 𝑟−𝐵𝑁(0001)∥𝑍𝑟𝐵2(0001) out-of-plane and 𝑟−𝐵𝑁(1120)∥𝑍𝑟𝐵2(1120) in-plane. Cross-section transmission electron microscopy (TEM) micrographs showed that epitaxial break down of r-BN film occurs approximatively after 10 nm, above which epitaxial growth proceeds only in limited area up to 80 nm of film thickness. Both XRD and TEM demonstrate the formation of carbon- and nitrogen-containing cubic inclusions at the ZrB<sub>2</sub> surface. Quantitative analysis from X-ray photoelectron spectroscopy of the r-BN films shows B/N ratios between 1.30 to 1.20 and an O content of 3 to 4 at.%. Plan-view scanning electron microscopy (SEM) images reveal a surface morphology where an amorphous material comprising B, C, and N is surrounding the epitaxial twinned r-BN crystals. SiH<sub>4</sub> exposure prior to growth was found to reduce the amount of the amorphous phase on the surface. Defects such as pitting were also observed on the ZrB<sub>2</sub> template surface.</div><div><br></div>

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Effect of Graphene Oxide Concentration in Electrolyte on Corrosion Behavior of Electrodeposited Zn–Electrochemical Reduction Graphene Composite Coatings

Coatings ◽

10.3390/coatings9110758 ◽

2019 ◽

Vol 9 (11) ◽

pp. 758 ◽

Cited By ~ 5

Author(s):

Yang ◽

Zhang ◽

Wang ◽

Chen ◽

...

Keyword(s):

Corrosion Behavior ◽

Electrochemical Impedance ◽

Composite Coatings ◽

Laser Raman Spectroscopy ◽

304 Stainless Steel ◽

Sulfate Electrolyte ◽

X Ray Diffraction ◽

X Ray ◽

Tafel Polarization ◽

Laser Raman

Pure Zn and Zn–ERGO composite coatings were prepared by direct current electrodeposition on 304 stainless steel. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDS), and laser Raman spectroscopy (Raman). Results obtained have shown that the concentration of GO sheets in zinc sulfate electrolyte has an important effect on the preferred crystal orientation and the surface morphology of Zn–ERGO composite coatings. A study of the corrosion behavior of the coatings by Tafel polarization and electrochemical impedance spectroscopic (EIS) methods leads to the conclusion that the Zn-1.0 g/L ERGO composite coating possesses the best corrosion resistance compared to the pure Zn coating and other composite coatings in this study.

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Amorphous Ni x Co y P-supported TiO2 nanotube arrays as an efficient hydrogen evolution reaction electrocatalyst in acidic solution

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.6 ◽

2019 ◽

Vol 10 ◽

pp. 62-70 ◽

Cited By ~ 5

Author(s):

Yong Li ◽

Peng Yang ◽

Bin Wang ◽

Zhongqing Liu

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Nanotube Arrays ◽

Active Surface Area ◽

X Ray ◽

Transmission Electron

Bimetallic phosphides have been attracting increasing attention due to their synergistic effect for improving the hydrogen evolution reaction as compared to monometallic phosphides. In this work, NiCoP modified hybrid electrodes were fabricated by a one-step electrodeposition process with TiO2 nanotube arrays (TNAs) as a carrier. X-ray diffraction, transmission electron microscopy, UV–vis diffuse reflection spectroscopy, X-ray photoelectron spectroscopy and scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy were used to characterize the physiochemical properties of the samples. The electrochemical performance was investigated by cyclic voltammetry, linear sweep voltammetry, and electrochemical impedance spectroscopy. We show that after incorporating Co into Ni–P, the resulting Ni x Co y P/TNAs present enhanced electrocatalytic activity due to the improved electron transfer and increased electrochemically active surface area (ECSA). In 0.5 mol L−1 H2SO4 electrolyte, the Ni x Co y P/TNAs (x = 3.84, y = 0.78) demonstrated an ECSA value of 52.1 mF cm−2, which is 3.8 times that of Ni–P/TNAs (13.7 mF cm−2). In a two-electrode system with a Pt sheet as the anode, the Ni x Co y P/TNAs presented a bath voltage of 1.92 V at 100 mA cm−2, which is an improvment of 79% over that of 1.07 V at 10 mA cm−2.

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