Influence of Element Penetration Region on Adhesion and Corrosion Performance of Ni-Base Coatings

In this study, Ni–P/Ni–P–SiC coatings were prepared on pretreated 45 steel substrates by scanning electrodeposition. Prior to the electrodeposition, the substrates were subjected to two types of pretreatments: polishing and sandblasting. The 3D morphology of the pretreated substrates was characterized by laser scanning confocal microscopy. The micromorphology and section morphology of the coating surface were characterized by field emission scanning electron microscopy. The section element composition was characterized using an EDS energy spectrum analyzer. The adhesion and corrosion resistance of 15 coatings were analyzed using an automatic scratch tester and CS350 electrochemical workstation. The results showed the presence of an element penetration region between the coating and the substrate. The sandblasting pretreatment and SiC nanoparticle addition helped widen the penetration region of the elements. The Ni–P–SiC coating prepared by scanning electrodeposition on the sandblasted substrate exhibited the thickest penetration region, up to 28.39 µm. A scratch test conducted on this coating showed that it exhibits the best adhesion force, up to 36.5 N. In electrochemical corrosion experiments, its corrosion potential was found to be the highest, reaching −0.30 V, and the corrosion current density was the lowest, reaching 8.45 × 10−7 A·cm−2. The presence of the element penetration region increased the coating adhesion and improved the corrosion resistance.

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Research on Corrosion Resistance of AZ91D Magnesium Alloy Coated with Epoxy Resin

Materials Science Forum ◽

10.4028/www.scientific.net/msf.686.292 ◽

2011 ◽

Vol 686 ◽

pp. 292-299

Author(s):

Yong Gang Li ◽

Ying Hui Wei ◽

Li Feng Hou ◽

Yun Tian ◽

Li Jing Yang

Keyword(s):

Corrosion Resistance ◽

Magnesium Alloy ◽

Adhesion Force ◽

Die Casting ◽

Corrosion Current ◽

Scratch Test ◽

Organic Coating ◽

Thin Wall ◽

Scanning Method ◽

Az91d Magnesium Alloy

The corrosion resistance of a 1~2mm thick AZ91D magnesium alloy die-casting coated with epoxy varnish after phosphatizing was tested. Zinc phosphating solution was used. In the experiment, uniform paint was obtained by dipping method. Scratch test showed that the adhesion force between the coating and matrix is excellent. Within the test range the optimal phosphating temperature and time are 50°C and 1 min tested by dynamic potential scanning method. With the organic coating the corrosion current density decreased 3 orders of magnitude, the polarization resistance increased 3 orders of magnitude. The coated specimens were immersed in10% H2SO4, 10% NaOH and acetone for 10 days, respectively. The results showed that blistering did not occur on the paint films. This work illustrated that the simple zinc phosphating process combined with simple organic coating can meet the corrosion resistance requirements of thin-wall die casting magnesium components that require higher quality appearance.

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Wear Behavior of Hard Dental Tissues and Restorative Materials

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.486.72 ◽

2013 ◽

Vol 486 ◽

pp. 72-77 ◽

Cited By ~ 1

Author(s):

Radim Ctvrtlik ◽

Jan Tomastik

Keyword(s):

Laser Scanning ◽

Wear Behavior ◽

Scratch Test ◽

Laser Scanning Confocal Microscopy ◽

Point Of View ◽

Human Teeth ◽

Scanning Confocal Microscopy ◽

Dental Tissues ◽

Restorative Materials ◽

Dental Restorative

Human teeth are exposed to various chemical and mechanical factors. From mechanical point of view it includes attrition, abrasion or their combination. Teeth and dental restorative materials are subjected to normal and shear loads. Therefore the contact-based stresses during mastication and teeth wear are of considerable importance. In order to study wear behavior of enamel, dentine and two dental restorative composite materials scratch test at various contact conditions was employed. Hardness and elastic modulus were measured using nanoindentation with spherical and pyramidal indenters. Residual wear tracks were observed using laser scanning confocal microscopy.

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Effect of Grit Blasting and Polishing Pretreatments on the Microhardness, Adhesion and Corrosion Properties of Electrodeposited Ni-W/SiC Nanocomposite Coatings on 45 Steel Substrate

Crystals ◽

10.3390/cryst11070729 ◽

2021 ◽

Vol 11 (7) ◽

pp. 729

Author(s):

Bertrand Vigninou Gbenontin ◽

Min Kang ◽

Ndumia Joseph Ndiithi ◽

Samuel Mbugua Nyambura ◽

Emmanuel Awuah ◽

...

Keyword(s):

Corrosion Resistance ◽

Laser Scanning ◽

Steel Substrate ◽

Laser Scanning Confocal Microscopy ◽

Nanocomposite Coatings ◽

X Ray Diffraction ◽

Corrosion Properties ◽

Grit Blasting ◽

Scanning Confocal Microscopy ◽

The One

In this study, a grit-blasting pretreatment was used to improve the adhesion, corrosion resistance and microhardness of Ni-W/SiC nanocomposite coatings fabricated using the conventional electrodeposition technique. Prior to deposition, grit blasting and polishing (more commonly used) pretreatments were used to prepare the surface of the substrate and the 3D morphology of the pretreated substrates was characterized using laser scanning confocal microscopy. The coating surface and the cross-section morphology were analyzed using scanning electron microscopy (SEM). The chemical composition, crystalline structure, microhardness, adhesion and corrosion behavior of the deposited coatings were characterized using energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), a microhardness tester, a scratch tester and an electrochemical workstation, respectively. The results indicated that the grit blasting and SiC addition improved the microhardness, adhesion and corrosion resistance. The Ni-W/SiC nanocomposites pretreated by grit blasting exhibited the best adhesion strength, up to 36.5 ± 0.75 N. Its hardness was the highest and increased up to 673 ± 5.47 Hv and its corrosion resistance was the highest compared to the one pretreated by polishing.

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Fabrication of Ni–Co–BN (h) Nanocomposite Coatings with Jet Electrodeposition in Different Pulse Parameters

Coatings ◽

10.3390/coatings9010050 ◽

2019 ◽

Vol 9 (1) ◽

pp. 50 ◽

Cited By ~ 1

Author(s):

Hengzheng Li ◽

Min Kang ◽

Yin Zhang ◽

Yuntong Liu ◽

Meifu Jin ◽

...

Keyword(s):

Corrosion Resistance ◽

Duty Cycle ◽

Laser Scanning ◽

Corrosion Current ◽

Pulse Frequency ◽

Laser Scanning Confocal Microscopy ◽

Nanocomposite Coatings ◽

Obvious Effect ◽

Pulse Parameters ◽

Jet Electrodeposition

In order to study the effects of pulse parameters on jet electrodeposition, Ni–Co–BN (h) nanocomposite coatings were prepared on the surface of steel C1045. The samples were analyzed and characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), laser scanning confocal microscopy (LSCM), microhardness tester, and electrochemical workstation. The experimental results showed that the contents of Co and BN (h) nanoparticles in the coatings changed with the variation of pulse parameters. When the pulse frequency was 4 kHz and the duty cycle was 0.7, their contents reached maxima of 27.34 wt % and 3.82 wt %, respectively. The XRD patterns of the coatings showed that the deposits had a face-centered cube (fcc) structure, and there was an obvious preferred orientation in (111) plane. With the increase in pulse parameters, the surface roughness of the coatings first decreased and then increased, with the minimum value obtained being 0.664 µm. The microhardness of the coatings first increased and then decreased with increase in pulse parameters. The maximum value of the microhardness reached 719.2 HV0.05 when the pulse frequency was 4 kHz and the duty cycle was 0.7. In the electrochemical test, the potentiodynamic polarization curves of the coatings after immersion in 3.5 wt % NaCl solution showed the pulse parameters had an obvious effect on the corrosion resistance of the Ni–Co–BN (h) nanocamposite coatings. The corrosion current density and polarization resistance indicated that the coatings had better corrosion resistance when the pulse frequency was 4 kHz and duty cycle was 0.7.

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Study on Preparation of Superhydrophobic Ni-Co Coating and Corrosion Resistance by Sandblasting–Electrodeposition

Coatings ◽

10.3390/coatings10121164 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1164

Author(s):

Zhengwei Zhang ◽

Zhenyu Shen ◽

Hongbin Wu ◽

Lingquan Li ◽

Xiuqing Fu

Keyword(s):

Contact Angle ◽

Corrosion Resistance ◽

Laser Scanning ◽

Three Dimensional ◽

Electrochemical Corrosion ◽

Corrosion Current ◽

X Ray Diffraction ◽

Water Contact ◽

Angle Measuring ◽

Surface Contact Angle

To enhance the corrosion resistance of type C45E4 substrates, a superhydrophobic Ni-Co coating was prepared on a C45E4 surface by sandblasting pretreatment and electrodeposition. The surface microstructure, three-dimensional surface roughness, and crystal structure of the coating was characterized by scanning electron microscope, laser scanning confocal microscope, and X-ray diffraction. An optical surface contact angle measuring instrument and an electrochemical workstation was used to characterize the wettability and corrosion resistance of the surface. The results showed that the water contact angle reached 151.2 degrees on the Ni-Co coating surface. The surface was superhydrophobic and still had stable hydrophobicity after four months. In electrochemical corrosion experiments. Compared with polishing pretreatment, the corrosion current density of superhydrophobic Ni-Co coating prepared by sandblasting pretreatment reached Icorr = 5.05 × 10−7 A·cm−2, and the corrosion potential reached Ecorr = −0.33 V. The superhydrophobic Ni-Co coating had excellent corrosion resistance.

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Effect of Grit Blasting and Polishing Pretreatments on the Microhardness, Adhesion and Corrosion Properties of Electrodeposited Ni-W/SiC Nanocomposite Coatings on 45 Steel Substrate

10.20944/preprints202106.0191.v1 ◽

2021 ◽

Author(s):

Gbenontin Vigninou Bertrand ◽

Min Kang ◽

Ndumia Joseph Ndiithi ◽

Samuel Mbugua Nyambura ◽

Awuah Emmual ◽

...

Keyword(s):

Corrosion Resistance ◽

Laser Scanning ◽

Steel Substrate ◽

Laser Scanning Confocal Microscopy ◽

Nanocomposite Coatings ◽

X Ray Diffraction ◽

Corrosion Properties ◽

Grit Blasting ◽

Scanning Confocal Microscopy ◽

The One

In this study, grit blasting pretreatment was used to improve the adhesion and corrosion resistance and microhardness of Ni-W/SiC nanocomposite coatings fabricated using conventional electrodeposition technique. Prior to deposition, grit blasting and polishing (more commonly used) pretreatment were used to prepare the surface of the substrate and the 3D morphology of the pretreated substrates was characterized using laser scanning confocal microscopy. The coatings surface and the cross section morphology were analyzed using scanning electron microscopy (SEM). The chemical composition, crystalline structure, microhardness, adhesion, and the corrosion behavior of the deposited coatings were characterized using energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), microhardness tester, scratch tester and electrochemical workstation, respectively. The results indicated that the grit blasting and SiC addition, improved the microhardness, adhesion and corrosion resistance. The Ni-W-SiC nanocomposites pretreated by grit blasting exhibited the best adhesion strength, up to 36.5 ± 0.75 N. Its hardness was the highest and increased up to 673 ± 5.47Hv and its corrosion resistance was the highest compared to the one pretreated by polishing.

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Laser Scanning Confocal Microscopy and Three-Dimesnsional Reconstruction of the Mitotic Spindles of Unequally Dividing Embryonic Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158376 ◽

1990 ◽

Vol 48 (3) ◽

pp. 166-167

Author(s):

J. Holy ◽

G. Schatten

Keyword(s):

Confocal Microscopy ◽

Mitotic Spindle ◽

Laser Scanning ◽

Three Dimensional ◽

Laser Scanning Confocal Microscopy ◽

Two Dimensions ◽

Embryonic Cells ◽

Mitotic Spindles ◽

Cleavage Division ◽

Scanning Confocal Microscopy

One of the classic limitations of light microscopy has been the fact that three dimensional biological events could only be visualized in two dimensions. Recently, this shortcoming has been overcome by combining the technologies of laser scanning confocal microscopy (LSCM) and computer processing of microscopical data by volume rendering methods. We have employed these techniques to examine morphogenetic events characterizing early development of sea urchin embryos. Specifically, the fourth cleavage division was examined because it is at this point that the first morphological signs of cell differentiation appear, manifested in the production of macromeres and micromeres by unequally dividing vegetal blastomeres.The mitotic spindle within vegetal blastomeres undergoing unequal cleavage are highly polarized and develop specialized, flattened asters toward the micromere pole. In order to reconstruct the three-dimensional features of these spindles, both isolated spindles and intact, extracted embryos were fluorescently labeled with antibodies directed against either centrosomes or tubulin.

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Automated 3-D cell population analysis in thick tissue sections using laser-scanning confocal-microscopy data

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148642 ◽

1993 ◽

Vol 51 ◽

pp. 562-563

Author(s):

Hakan Ancin

Keyword(s):

Laser Scanning ◽

Population Analysis ◽

Three Dimensional ◽

Large Data ◽

Laser Scanning Confocal Microscopy ◽

Tissue Slices ◽

Scanning Confocal Microscopy ◽

Tissue Sections ◽

Spatially Adaptive ◽

Microscopy Data

This paper presents methods for performing detailed quantitative automated three dimensional (3-D) analysis of cell populations in thick tissue sections while preserving the relative 3-D locations of cells. Specifically, the method disambiguates overlapping clusters of cells, and accurately measures the volume, 3-D location, and shape parameters for each cell. Finally, the entire population of cells is analyzed to detect patterns and groupings with respect to various combinations of cell properties. All of the above is accomplished with zero subjective bias.In this method, a laser-scanning confocal light microscope (LSCM) is used to collect optical sections through the entire thickness (100 - 500μm) of fluorescently-labelled tissue slices. The acquired stack of optical slices is first subjected to axial deblurring using the expectation maximization (EM) algorithm. The resulting isotropic 3-D image is segmented using a spatially-adaptive Poisson based image segmentation algorithm with region-dependent smoothing parameters. Extracting the voxels that were labelled as "foreground" into an active voxel data structure results in a large data reduction.

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Advanced Static and Dynamic Fluorescence Microscopy Techniques to Investigate Drug Delivery Systems

Pharmaceutics ◽

10.3390/pharmaceutics13060861 ◽

2021 ◽

Vol 13 (6) ◽

pp. 861

Author(s):

Jacopo Cardellini ◽

Arianna Balestri ◽

Costanza Montis ◽

Debora Berti

Keyword(s):

Drug Delivery ◽

Fluorescence Microscopy ◽

Drug Delivery Systems ◽

Laser Scanning ◽

Super Resolution ◽

Laser Scanning Confocal Microscopy ◽

Delivery Systems ◽

Scanning Confocal Microscopy ◽

Biological Phenomena

In the past decade(s), fluorescence microscopy and laser scanning confocal microscopy (LSCM) have been widely employed to investigate biological and biomimetic systems for pharmaceutical applications, to determine the localization of drugs in tissues or entire organisms or the extent of their cellular uptake (in vitro). However, the diffraction limit of light, which limits the resolution to hundreds of nanometers, has for long time restricted the extent and quality of information and insight achievable through these techniques. The advent of super-resolution microscopic techniques, recognized with the 2014 Nobel prize in Chemistry, revolutionized the field thanks to the possibility to achieve nanometric resolution, i.e., the typical scale length of chemical and biological phenomena. Since then, fluorescence microscopy-related techniques have acquired renewed interest for the scientific community, both from the perspective of instrument/techniques development and from the perspective of the advanced scientific applications. In this contribution we will review the application of these techniques to the field of drug delivery, discussing how the latest advancements of static and dynamic methodologies have tremendously expanded the experimental opportunities for the characterization of drug delivery systems and for the understanding of their behaviour in biologically relevant environments.

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