Effect of Ni Addition on the Corrosion Resistance of NiTi Alloy Coatings on AISI 316L Substrate Prepared by Laser Cladding

In this paper, an equiatomic NiTi (55NiTi) alloy powder was mixed with pure Ni powder to prepare laser cladding coatings on a 316L stainless steel substrate to study the effect of Ni addition on the microstructure and corrosion resistance of the coatings. The microstructure and phase composition of the coatings were analyzed using a scanning electron microscope (SEM) with configured energy-dispersive spectrometer (EDS) and X-ray diffractometer (XRD). OCP (open-circuit potential), PD (potentiodynamic polarization) and EIS (electrochemical impedance spectroscopy) experiments were conducted by a Gamry electrochemical workstation, and corresponding eroded morphologies were observed to evaluate the coating’s anti-corrosion performance. The addition of Ni led to fine and uniform dendrites and dense microstructure under the metallurgical microscope, which were beneficial for the formation of the passive film mainly consisting of titanium dioxide (TiO2). The results show that the pitting potential of the 55NiTi + 5Ni coating was 0.11 V nobler than that of the 55NiTi coating, and the corrosion current density was less than half that of the 55NiTi coating. The corrosion initiated preferentially at the interfaces of dendrites and inter-dendritic areas, then spread first to dendrites rather than in the inter-dendritic areas.

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Influence of Ultrasonic Excitation Sealing on the Corrosion Resistance of HVOF-Sprayed Nanostructured WC-CoCr Coatings under Different Corrosive Environments

Coatings ◽

10.3390/coatings9110724 ◽

2019 ◽

Vol 9 (11) ◽

pp. 724 ◽

Cited By ~ 9

Author(s):

Zhang ◽

Hong ◽

Lin ◽

Zheng

Keyword(s):

Corrosion Resistance ◽

Atmospheric Pressure ◽

Room Temperature ◽

Open Circuit Potential ◽

Electrochemical Impedance ◽

Corrosion Current ◽

Aluminum Phosphate ◽

Open Circuit ◽

Corrosive Environments ◽

Oxygen Fuel

The corrosion behavior of unsealed and sealed high-velocity oxygen-fuel (HVOF)-sprayed nanostructured WC-CoCr cermet coatings under different corrosive environments was investigated using scanning electron microscopy (SEM), open circuit potential (OCP), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Ultrasonic excitation sealing with aluminum phosphate was performed in an external ultrasonic bath with the frequency of 40 kHz at atmospheric pressure and room temperature. SEM micrographs revealed that the exposed area of the coating was effectively reduced by the coverage of aluminum phosphate sealant on the majority of pores. Electrochemical measurements demonstrated that the sealant with the help of ultrasonic energy could shift the corrosion potential to a more noble direction, reduce the corrosion current density, increase the resistance of charge transfer, and effectively improve the corrosion resistance of the coating in both 3.5 wt % NaCl and 1 mol·L−1 HCl solutions.

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Influence of Thermal Treatment on the Structure and the Corrosion Resistance of Zn-Ni Alloy Coatings

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.203-204.224 ◽

2013 ◽

Vol 203-204 ◽

pp. 224-227

Author(s):

Magdalena Popczyk ◽

Bożena Łosiewicz ◽

Grzegorz Dercz ◽

Agnieszka Smołka

Keyword(s):

Corrosion Resistance ◽

Thermal Treatment ◽

Surface Morphology ◽

Steel Substrate ◽

Diffraction Method ◽

Corrosion Current ◽

Potential Method ◽

Open Circuit ◽

X Ray ◽

Ni Alloy

Electrolytic Zn-Ni alloy coatings were obtained on the steel substrate under galvanostatic conditions, and then, subjected to thermal treatment in argon atmosphere. The influence of thermal treatment on the surface morphology, phase composition and corrosion resistance of the electrodeposited coatings has been studied. Surface morphology was examined using a scanning electron microscopy. Chemical composition was determined by a X-ray fluorescence spectroscopy. Structural studies were carried out using a X-ray diffraction method. Corrosion resistance tests were carried out in 3% NaCl solution using open circuit potential method and potentiodynamic measurements. It was found that after thermal treatment, the value of polarization resistance increases, the value of the corrosion current decreases, and the value of corrosion potential is shifted towards anodic potentials. This suggests a positive effect of thermal treatment of the Zn-Ni alloy coatings on their corrosion resistance.

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Corrosion and Micromorphological Analysis of Temporary Stainless Steel and Titanium Alloy Anchorage Devices

10.31224/osf.io/8abtx ◽

2020 ◽

Author(s):

Carolina Assis do Nascimento

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Titanium Alloy ◽

Electrochemical Impedance ◽

Corrosion Current ◽

Open Circuit ◽

X Ray ◽

Potentiodynamic Polarization Curves ◽

Surface Micromorphology ◽

Micromorphological Analysis

The aim of this study was to compare the surface micromorphology and corrosion resistance of diferent temporary anchoragedevices (TADs) composed of titanium alloy (SIN®) and stainless steel (DAT Steel® and Bio Ray®). Ten samples of eachTAD were submitted to qualitative analyses using energy-dispersive and scanning electronic microscopy before and afterimmersion in artifcial saliva (1500 ppm of fuoride) for 30 days. The chemical analysis was done by X-ray fuorescence,and the corrosion tests were performed by electrochemical means (open circuit potential—OCP, potentiostat, and electrochemical impedance spectroscopy—EIS, using anodic potentiodynamic polarization curves). Passive flm resistance (PFR)and corrosion current were established. The corrosion rate was determined by the mass loss test. Greater smoothness andfewer machining defects were observed for the stainless steel TAD before artifcial saliva immersion. Comparatively, highercorrosion resistance was found for titanium alloy TAD after immersion in saliva. There was no release of ions into the TADwhen immersed in artifcial saliva. ANOVA and Tukey tests showed that OCP (V) was signifcantly lower for the titaniumalloy TAD (p=0.030) than the stainless steel brands. Epite (V) and Epite−OCP (V) were signifcantly higher for the titaniumalloy TAD (p=0.0009 and p=0.0005, respectively). Stainless steel TADs presented lower roughness surface than titaniumalloy TAD, although the latter presented higher corrosion resistance than the former

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Laser cladding of Ni60 + 17 − 4PH composite for a cracking-free and corrision resistive coating

International Journal of Modern Physics B ◽

10.1142/s0217979220400421 ◽

2019 ◽

Vol 34 (01n03) ◽

pp. 2040042

Author(s):

Zhaohui Chen ◽

Ruifeng Li ◽

Jiayang Gu ◽

Zhongyu Zhang ◽

Yanwu Tao ◽

...

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Corrosion Resistance ◽

Laser Cladding ◽

Steel Substrate ◽

Corrosion Current ◽

Characterization Methods ◽

Surface Cracking ◽

Mechanical Properties And Corrosion ◽

1045 Steel

In order to obtain a laser-cladded coating with no cracking and good corrosion resistance, this paper investigated laser cladding of a mixture of 17-4PH stainless steel and Ni60 powders on ASTM 1045 steel substrate. The surface cracking, mechanical properties and corrosion resistance of the coatings were assessed by various characterization methods. The experimental results demonstrated that a crack-free coating can be obtained by adding 30% (or above) 17-4PH stainless steel into Ni60 alloy. The mechanical properties of the coatings were determined by adding 17-4PH, but stabilized at about 79% of pure Ni60 alloy, which is acceptable considering the benefit of elimination of surface cracking. Decrease in the mechanical properties were caused by the dilution of the strengthening elements and reduction of population of hard phases. Composite coating having 30% of 17-4PH also exhibited the smallest corrosion current, lowest corrosion potential and slowest corrosion rate, and therefore the best corrosion resistance.

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Comparative Investigation on Corrosion Resistance of Stainless Steels Coated with Titanium Nitride, Nitrogen Titanium Carbide and Titanium-Diamond-like Carbon Films

Coatings ◽

10.3390/coatings11121543 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1543

Author(s):

Jia Lou ◽

Zonglong Gao ◽

Jie Zhang ◽

Hao He ◽

Xinming Wang

Keyword(s):

Corrosion Resistance ◽

Titanium Carbide ◽

Titanium Nitride ◽

Electrochemical Impedance ◽

High Volume ◽

Corrosion Current ◽

Comparative Investigation ◽

Carbon Films ◽

Open Circuit ◽

Diamond Like Carbon

In this study, the corrosion resistance of titanium nitride (TiN), nitrogen titanium carbide (TiCN) and titanium-diamond-like carbon (Ti-DLC) films deposited on 316L stainless steel (SS) were compared via differences in the surface and section-cross morphologies, open circuit potential tests, electrochemical impedance spectroscopy and potentiometric tests. The corrosion resistance of the TiCN and Ti-DLC films significantly improved because of the titanium carbide (TiC) crystals that obstruct the corrosive species penetrating the as-deposited film in the electrolyte atmosphere. TiN exhibited the lowest corrosion resistance because of its low thickness and high volume of defects. The Ti-DLC film showed the lowest corrosion current density (approximately 4.577 μA/cm2) and thickness reduction (approximately 0.12 μm) in different electrolytes, particularly those with high Cl− and H+ concentrations, proving to be the most suitable corrosion protection material for 316L SS substrates.

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Corrosion Resistance Test of Electroplated Gold and Palladium Using Fast Electrochemical Analysis

Coatings ◽

10.3390/coatings9060405 ◽

2019 ◽

Vol 9 (6) ◽

pp. 405

Author(s):

Walter Giurlani ◽

Patrick Marcantelli ◽

Francesco Benelli ◽

Daniele Bottacci ◽

Filippo Gambinossi ◽

...

Keyword(s):

Corrosion Resistance ◽

Standardized Tests ◽

Open Circuit Potential ◽

Electrochemical Impedance ◽

Salt Spray ◽

Corrosion Current ◽

Electrochemical Analysis ◽

Open Circuit ◽

Metal Coatings ◽

High Impedance

Noble metal coatings are commonly employed to improve corrosion resistance of metals in the electronic and jewellery industry. The corrosion resistance of electroplated goods is currently determinate with long, destructive and almost subjective interpretation corrosion tests in artificial atmosphere. In this study we present the application of electrochemical analysis to obtain fast and numerical information of the antiaging coating. We performed open circuit potential (OCP) and corrosion current measurement; we employed also the electrochemical impedance spectroscopy (EIS), commonly applied to organic or passivated metal with high-impedance, to find the best option for noble low-impedance coating analysis. For comparison, traditional standardized tests (damp heat ISO 17228, salt spray ISO 9227 and sulphur dioxide ISO 4524) were also performed.

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Effect of Incorporating MoS2 in Organic Coatings on the Corrosion Resistance of 316L Stainless Steel in a 3.5% NaCl Solution

Coatings ◽

10.3390/coatings9010045 ◽

2019 ◽

Vol 9 (1) ◽

pp. 45 ◽

Cited By ~ 9

Author(s):

Min-Sung Hong ◽

Yunjeong Park ◽

Jung Kim ◽

Kyunghoon Kim

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

316L Stainless Steel ◽

Electrochemical Impedance ◽

Energy Dispersive Spectrometer ◽

Open Circuit ◽

Coating Film ◽

Nacl Solution ◽

Coating Method ◽

Coating Durability

This study discusses a new coating method to protect 316L stainless steel (SS) from pitting corrosion in high chloride environments. The SS surface was coated using a simple, eco-friendly method, and sunflower oil (SunFO) was used as a base coating and binder for molybdenum disulfide (MoS2). The coated surface was observed using scanning electron microscopy (SEM) with an energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). Corrosion behavior was examined by open-circuit potential (OCP) measurement and electrochemical impedance spectroscopy (EIS) in an 3.5% NaCl solution. The SunFO coating with MoS2 showed the highest corrosion resistance and coating durability during the immersion time relative to the SunFO coating and bare 316L SS. The increased corrosion resistance is thought to be because of the interactions with the aggregations of the SunFO lamellar structure and MoS2 in the coating film, which acted as a high order layer barrier providing protection from the metals to electrolytes.

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The Influence of Sodium Molybdate on the Properties of Zn-Ni Layers Obtained by Electrolytic Deposition

Materials Science Forum ◽

10.4028/www.scientific.net/msf.636-637.1053 ◽

2010 ◽

Vol 636-637 ◽

pp. 1053-1058 ◽

Cited By ~ 3

Author(s):

Katarzyna Wykpis ◽

Antoni Budniok ◽

Eugeniusz Łągiewka

Keyword(s):

Corrosion Resistance ◽

Chemical Composition ◽

Surface Morphology ◽

Electrochemical Impedance ◽

Chemical Elements ◽

Steel Substrate ◽

Sodium Molybdate ◽

Open Circuit ◽

Electrolytic Deposition ◽

Structural Investigations

This study was undertaken in the aim to try the limit of extraction of Zn from Zn-Ni system. The aim was realized by the addition of MoO42- ions into the galvanic bath containing Ni2+ and Zn2+ ions. Zn-Ni-Mo layers were deposited under galvanostatic conditions on (OH18N9) austenitic steel substrate. The influence of Na2MoO4 concentration in a bath on the surface morphology, chemical and phase composition and the corrosion resistance of obtained layers, was investigated. The properties of Zn-Ni-Mo layers were compared to the properties of electrolytic Zn-Ni layer. Structural investigations were performed by the X-ray diffraction (XRD) method. The surface morphology and chemical composition and surface chemical elements distribution of deposited layers were studied using a scanning electron microscope. Electrochemical corrosion resistance investigations were done by classical Stern method and electrochemical impedance spectroscopy. The potentiodynamic curves in the range of  0.05V to the potential of open circuit, were obtained. On the base of these curves the parameters like corrosion potential- Ecor, corrosion current density- icor and the polarization resistance- Rp were determined. These values served as a measure of the corrosion resistance of obtained layers. Results of impedance investigations were presented on the Nyquist Z”= f (Z’) and the Bode log Z = f (log) and  = f (log), diagrams. On the basis on this research, it was exhibited that surface morphology, chemical composition of Zn-Ni-Mo layers are dependent on Mo contents. The optimal content of Na2MoO4 in the bath for the sake of corrosion resistance in 5% NaCl, is found to be 1.2 gdm-3.

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Sacrificial Dissolution of Zinc Electroplated and Cold Galvanized Coated Steel in Saline and Soil Environments: A Comparison

Materials ◽

10.3390/ma14040744 ◽

2021 ◽

Vol 14 (4) ◽

pp. 744

Author(s):

Ameeq Farooq ◽

Umer Masood Chaudry ◽

Ahsan Saleem ◽

Kashif Mairaj Deen ◽

Kotiba Hamad ◽

...

Keyword(s):

Corrosion Rate ◽

Electrochemical Impedance ◽

Saline Soil ◽

Steel Substrate ◽

Salt Spray ◽

Steel Structures ◽

Open Circuit ◽

Cyclic Polarization ◽

Transfer Resistance ◽

Soil Solutions

To protect steel structures, zinc coatings are mostly used as a sacrificial barrier. This research aims to estimate the dissolution tendency of the electroplated and zinc-rich cold galvanized (ZRCG) coatings of a controlled thickness (35 ± 1 μm) applied via brush and dip coating methods on the mild steel. To assess the corrosion behavior of these coated samples in 3.5% NaCl and 10% NaCl containing soil solutions, open circuit potential (OCP), cyclic polarization (CP), and electrochemical impedance spectroscopy (EIS) tests were performed. The more negative OCP and appreciably large corrosion rate of the electroplated and ZRCG coated samples in 3.5% NaCl solution highlighted the preferential dissolution of Zn coatings. However, in saline soil solution, the relatively positive OCP (>−850 mV vs. Cu/CuSO4) and lower corrosion rate of the electroplated and ZRCG coatings compared to the uncoated steel sample indicated their incapacity to protect the steel substrate. The CP scans of the zinc electroplated samples showed a positive hysteresis loop after 24 h of exposure in 3.5% NaCl and saline soil solutions attributing to the localized dissolution of the coating. Similarly, the appreciable decrease in the charge transfer resistance of the electroplated samples after 24 h of exposure corresponded to their accelerated dissolution. Compared to the localized dissolution of the electroplated and brush-coated samples, the dip-coated ZRCG samples exhibited uniform dissolution during the extended exposure (500 h) salt spray test.

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Study on the Effect of Ni Addition on the Microstructure and Properties of NiTi Alloy Coating on AISI 316 L Prepared by Laser Cladding

Materials ◽

10.3390/ma14164373 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4373

Author(s):

Yuqiang Feng ◽

Zexu Du ◽

Zhengfei Hu

Keyword(s):

Laser Cladding ◽

Niti Alloy ◽

Second Phase ◽

Content Increase ◽

Strengthening Effect ◽

Mixed Powder ◽

Microstructure And Properties ◽

Cladding Layer ◽

Ni Addition ◽

Aisi 316 L

This paper investigated 55 NiTi commercial alloy powder and 55 NiTi with 5% pure Ni mixed powder (55 NiTi + 5 Ni) coatings fabricated by laser cladding to study the effect of extra Ni addition on the microstructure and properties of the coating. The XRD and EDS results show that the major phases in the coatings were NiTi and Ni3Ti. Besides that, a second phase like Ni4Ti3, Fe2Ti, and NiTi2 was also detected, among which, NiTi2 was only found in 55 NiTi coating. The proportion of the phase composition in the coating was calculated via the software Image-Pro Plus. The hardness of the cladding layer reaches 770–830 HV, which was almost four times harder than the substrate, and the hardness of 55 NiTi + 5 Ni coating was around 8% higher than that of 55 NiTi coating. The wear resistance of the 55 NiTi + 5 Ni coating was also better; the wear mass loss decreased by about 13% and with a smaller friction coefficient compared with the 55 NiTi coating. These results are attributed to the solid solution strengthening effect caused by Ni addition and the second phase strengthening effect caused by the content increase of the Ni3Ti phase in the cladding layer.

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