scholarly journals Two-stage PVD method for protective coating formation

2021 ◽  
Vol 2064 (1) ◽  
pp. 012074
Author(s):  
V A Burdovitsin ◽  
A V Tyunkov ◽  
Y G Yushkov ◽  
D B Zolotukhin
Keyword(s):  
Aluminum Oxide ◽  
Protective Coating ◽  
Titanium Substrate ◽  
Protective Layer ◽  
Substrate Material ◽  
Two Stage ◽  
Layered Coatings ◽  
Intermediate Layers ◽  
Coating Formation ◽  
Electron Beam Transport

Abstract The CVD methods are typically used for the formation of aluminum oxide coatings since aluminum oxide is a dielectric. The adhesion between the protective coating and the substrate material is normally improved by growing thin intermediate layers based on titanium oxides and nitrides. These intermediate layers are mainly formed using the PVD methods. In this paper, we propose a two-stage PVD method for forming a layered structure on the titanium substrate. The formation of intermediate layers was carried out by the magnetron method (first stage), and the main protective layer was deposited at the second stage using a fore-vacuum electron source. The dense beam plasma generated during the electron beam transport in a fore-vacuum gas medium compensates for the negative electrical charge accumulating on the surface of the aluminum oxide target and facilitates its effective evaporation. The electrical properties of the intermediate layers and the resulting layered coatings have been investigated, including the tangent of dielectric loss angle, the real and imaginary parts of the conductivity and the dielectric constant dependencies on frequency.

scholarly journals Part II. Model for the Protective Coating Formation During Hot Dip Galvanizing/ Część II. Model Formowania Powłoki Ochronnej Podczas Cynkowania Ogniowego

2014 ◽  
Vol 59 (4) ◽  
pp. 1393-1404 ◽  
Author(s):  
W. Wołczynski ◽  
Z. Pogoda ◽  
G. Garzeł ◽  
B. Kucharska ◽  
A. Sypien ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Mass Balance ◽  
Protective Coating ◽  
Mathematical Description ◽  
Ternary Phase ◽  
Ternary Phase Diagram ◽  
Solute Redistribution ◽  
Zinc Bath ◽  
Flux System ◽  
Coating Formation

Abstract A mathematical description for the (Zn) - coating formation with the presence of flux in the zinc bath is presented. This description includes the progressive vanishing of the products of the flux disintegration. A function which expresses the flux vanishing is formulated. The solidification of some phase sub-layers in the (Zn) - coating is considered with the use of a hypothetical pseudo-ternary phase diagram Fe-Zn-flux. Some relationships are formulated to define the varying Zn - solute redistribution as observed across the sub-layers. The relationships are based on the mass balance analyzed for the coating / bath / flux system. An amount of the growing phase in a given sub-layers is also defined mathematically.

scholarly journals Features of the Surface and Subsurface Waves Application for Ultrasonic Evaluation of Physicomechanical Properties of Solids. Part 1. Influence of the Geometrical Parameters

2018 ◽  
Vol 9 (4) ◽  
pp. 325-326
Author(s):  
A. R. Baev ◽  
A. L. Mayorov ◽  
M. V. Asadchaya ◽  
V. N. Levkovich ◽  
K. G. Zhavoronkov
Keyword(s):  
Protective Coating ◽  
Layer Structure ◽  
Base Material ◽  
Protective Layer ◽  
Body Waves ◽  
Measuring System ◽  
Geometrical Parameters ◽  
Small Aperture ◽  
Ultrasonic Evaluation

Application of surface and subsurface waves for control of objects with a double-layer structure allows to extend possibilities of diagnostics of their physico-mechanical properties. The purpose of work was to determine conditions and offer recommendations providing measuring of ultrasonic velocity and amplitude of the former modes in protective layers and in basis of object at one-sided access to its surface.The analysis of an acoustic path of a measuring system in relation to ultrasonic evaluation of the objects having the restricted sizes and the protective coating according to velocity data of the surface and subsurface waves propagation is made. On the basis of representations of beam acoustics the dependences connecting a wavelength of the excited surface and subsurface modes, thickness and width of a controlled object, acoustic base of a sounding are defined. There are to provide a condition leveling of the influence of an acoustical noise created by the reflected and accompanying waves on parameters of acoustic signal with the given quantity of oscillations in an impulse.The principle opportunity is shown and conditions for determination of velocity of subsurface body waves in the base material which is under a protective coating layer are established. For these purposes on the basis of use of the block of ultrasonic probes the optimum scheme of a sounding is offered and the analytical expression for calculation of required velocity considering varying of thickness of a covering is received.The method of acoustical measuring realized by a direct and reverse sounding of the objects with small aperture and angle probes was analysed and formulas for determination of speed of subsurface wave under protective layer of the wedge form have been got. An ultrasonic device is suggested for the excitationreception of subsurface waves with different speed in objects (on 20–35 %) using for the acoustic concordance of environments of metallic sound duct as a wedge. Possibility of leveling of interference in a protective layer to control efects in basis of material by a volume wave by creation of supporting echo-signal of longitudinal wave of the set frequency and entered normally to the surface of object was studied.

A Novel Method for Refurbishing Used Hot Section Gas Turbine Blades

1995 ◽  
Vol 117 (1) ◽  
pp. 166-171 ◽  
Author(s):  
A. Kempster ◽  
N. Czech
Keyword(s):  
Gas Turbine ◽  
Turbine Blades ◽  
Protective Layer ◽  
Substrate Material ◽  
Corrosion Products ◽  
Normal Operation ◽  
Blade Surface ◽  
Gas Turbine Blades ◽  
Service Period ◽  
Novel Method

During the normal operation of a land-based gas turbine, attack will occur of the gas-washed surfaces of the rotating stationary blades in the turbine hot section. This attack and its intensity can be variable depending on the blade’s position in the turbine hot section. This attack will progressively degrade these gas-washed surfaces even if these surfaces have been previously coated with a protective layer. During the service period of the turbine, it will be necessary to refurbish the blades from the hotter section of the turbine. One of the refurbishment steps will be to provide the blades with a suitable replacement coating to afford protection until the next service period. Conventional refurbishment techniques used to clean the blade surface rely on abrasive cleaning and / or chemical pickling. These processes may be capable of removing superficial oxidation and any residual coating but are not able consistently to remove the substrate material that has suffered from corrosive attack. It is important that this attacked substrate layer be removed completely, otherwise any residual corrosion products, particularly the presence of deeply penetrated sulfides in grain boundaries, could significantly reduce the life of any subsequent coating. The technique described in this paper essentially activates the surface layer of the substrate that is corroded, thus rendering it more easily removed by chemical and physical means. It is possible by this method to remove up to 400 μm of the substrate material and provided that all the corrosion products are contained within this zone, it is demonstrated how this produces a clean unattacked surface that is necessary for any subsequent welding, brazing, or recoating operation.

scholarly journals Laser-Induced Color Marking of Titanium: A Modeling Study of the Interference Effect and the Impact of Protective Coating

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
K. M. Łęcka ◽  
M. R. Wójcik ◽  
A. J. Antończak
Keyword(s):  
Protective Coating ◽  
Interference Effect ◽  
Color Change ◽  
Protective Layer ◽  
Real Data ◽  
Thin Layers ◽  
Target Color ◽  
Additional Layer ◽  
The Impact ◽  
Modeling Study

Laser-induced color marking of metals, due to numerous advantages, including inter alia the high quality, resolution, durability, and noncontact methodology of surface marking, seems to be attractive for use in various applications. In this method, the resulting color is mainly evident from the interference effect. Therefore, one of the still unsolved problems on titanium is the color change after imposition of an additional layer (fingerprints, grease, etc.). In this paper, a computer simulation based on the theoretical thin layers model was presented. The results of the modeling study revealed that theoretically a thin protective coating of a known refractive index can be applied while still maintaining the target color. In this case, as a protective layer, an amphiphobic coating has been taken into consideration with its ability to resist surface contamination. The study was performed for titanium (grade 2). The model utilizes the real data derived from the spectrophotometer, as well as from the ellipsometry measurements of laser-induced samples.

scholarly journals The Effect of Antimony in the Intermediate IrO2-SnO2-Sb2O5 Oxide Layer on Titanium Substrate for Oxygen Evolution Mn1-x-yMoxSnyO2+x Anodes in Seawater Electrolysis

1970 ◽  
Vol 23 ◽  
pp. 21-32
Author(s):  
Jagadeesh Bhattarai
Keyword(s):  
Oxide Layer ◽  
Oxygen Evolution ◽  
Intermediate Layer ◽  
Electronic Conductivity ◽  
Titanium Substrate ◽  
Coating Solution ◽  
Intermediate Layers ◽  
Initial Oxygen ◽  
Co2 Recycling ◽  
Seawater Electrolysis

An attempt is made to find out the optimal compositions for the intermediate oxide layer of IrO2-SnO2-Sb2O5 in preventing insulating titanium oxide formation on titanium substrate for the oxygen evolution Mn1-x-yMoxSnyO2+x anodes in electrolysis of 0.5 M NaCl of pH 1 at 1000 A.m-2. Effects of antimony and iridium in the intermediate IrO2-SnO2-Sb2O5 layer are discussed. The 75 % of the iridium content in the intermediate layer of the oxygen evolution anodes can be substituted by SnO2 and small amount of Sb2O5 to increase the electronic conductivity of the intermediate layer as well as the activity of the Mn1-x-yMoxSnyO2+x/IrO2-SnO2-Sb2O5/Ti anodes for seawater electrolysis at pH 1. Although Sb5+ addition is effective in decreasing the Ir4+ concentration in the intermediate layer of the anodes, the Ir1-x-ySnxSbyO2+0.5y intermediate layers with the Sb5+/Sn4+ between 0.125-0.285 in the coating solution showed excellent performance of the oxygen evolution efficiency. All the examined manganese-molybdenum-tin triple oxides, Mn1-x-yMoxSnyO2+x, prepared by anodic deposition on the IrO2-SnO2-Sb2O5-coated titanium substrate showed around 99% initial oxygen evolution efficiency at a current density of 1000 A.m-2 in 0.5 M NaCl of pH 1 at 25ºC.Keywords: global CO2 recycling, hydrogen production electrode, IrO2-SnO2-Sb2O5 layer, 0.5 M NaCl, titanium substrate.DOI: 10.3126/jncs.v23i0.2093J. Nepal Chem. Soc., Vol. 23, 2008/2009Page: 21-32

Multi-Component Coatings Formation on Polycathode Magnetron Sputtering Systems

2017 ◽  
Vol 265 ◽  
pp. 166-170
Author(s):  
V.V. Kolesnik ◽  
Yu.K. Rubanov ◽  
Yu.E. Tokach
Keyword(s):  
Chemical Composition ◽  
Magnetron Sputtering ◽  
Coating Thickness ◽  
Diffusion Zone ◽  
Chemical Elements ◽  
Substrate Material ◽  
Coating Materials ◽  
Surface Microrelief ◽  
X Ray ◽  
Coating Formation

The results of experiments aimed at obtaining multi-component coatings, having a wider range of properties compared to single-component coatings, are provided. The process of formation of coating based on multi-component alloy Co (18...20%)-Cr (5...7%)-Al (0.3...0.4%)-Y(0.2...0.5) was studied. The chemical composition and thickness of the coating as well as the state of the transition layer were also studied. The results of electron probing and X-ray fluorescence microanalysis of obtained coatings are provided. This paper also demonstrates that the properties of surface microrelief are determined by the conditions of coating formation; that each sample of coating has similar sets of chemical elements, that their concentration depends on the precipitation conditions, chemical elements are equally distributed along the thickness of samples, and the diffusion zone of coating materials and substrate is almost non-existent. The low content of substrate material was found in obtained coatings. As the coating thickness increased, the content of substrate material decreased sharply.

scholarly journals A Novel Method for Refurbishing Used Hot Section Gas Turbine Blades

1993 ◽  
Author(s):  
Adrian Kempster ◽  
Norbert Czech
Keyword(s):  
Gas Turbine ◽  
Turbine Blades ◽  
Protective Layer ◽  
Substrate Material ◽  
Corrosion Products ◽  
Normal Operation ◽  
Blade Surface ◽  
Gas Turbine Blades ◽  
Service Period ◽  
Novel Method

During the normal operation of a land based gas turbine attack will occur of the gas washed surfaces of the rotating and stationary blades in the turbine hot section. This attack and its intensity can be variable depending on the blades position in the turbine hot section. This attack will progressively degrade these gas washed surfaces even if these surfaces have been previously coated with a protective layer. During the service period of the turbine, it will be necessary to refurbish the blades from the hotter section of the turbine. One of the refurbishment steps will be to provide the blades with a suitable replacement coating to afford protection until the next service period. Conventional refurbishment techniques used to clean the blade surface rely on abrasive cleaning and/or chemical pickling. These processes may be capable of removing superficial oxidation and any residual coating but are not able to consistently remove the substrate material that has suffered from corrosive attack. It is important that this attacked substrate layer is removed completely otherwise any residual corrosion products, particularly the presence of deeply penetrated sulphides in grain boundaries, could significantly reduce the life of any subsequent coating. The technique described in this Paper essentially activates the surface layer of the substrate that is corroded, thus rendering it more easily removed by chemical and physical means. It is possible by this method to remove up to 400 microns of the substrate material and provided that all the corrosion products are contained within this zone, it is demonstrated how this produces a clean unattacked surface that is necessary for any subsequent welding, brazing or recoating operation.

scholarly journals New Flexible Protective Coating for Printed Smart Textiles

2021 ◽  
Vol 11 (2) ◽  
pp. 664
Author(s):  
Valérie Bartsch ◽  
Volkmar von Arnim ◽  
Sven Kuijpens ◽  
Michael Haupt ◽  
Thomas Stegmaier ◽  
...  
Keyword(s):  
Protective Coating ◽  
Food Packaging ◽  
Statistical Design ◽  
Protective Layer ◽  
Water Vapor Permeability ◽  
Barrier Properties ◽  
Layered Silicates ◽  
Vapor Permeability ◽  
Statistical Design Of Experiments ◽  
Smart Textiles

In the field of food packaging, the addition of exfoliated layered silicates in polymers has been established to improve the polymers’ gas barrier properties. Using these polymers as coatings to protect smart textiles from oxidation and corrosion while maintaining their textile properties should significantly extend their lifetime and promote their market penetration. The aim of this study was to print new polymer dispersions containing layered silicates to protect screen-printed conductive structures, and to test the resulting samples. For this, appropriate printing parameters were determined by statistical design of experiments. According to these results, conductive structures were printed and protected with the selected coating. The abrasion resistance and the continuity of the protective layer of the printed samples were then measured. A continuous protective coating of approximately 70–80 µm thickness was applied on a conductive structure. The printed samples showed a very high resistance to abrasion (unchanged by 85,000 abrasion cycles) while remaining flexible and presenting a lower water vapor permeability (<2.5 g/m² d) than the coatings commonly used in the textile field.

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