scholarly journals The Influence of Organically Modified Derivatives of Silica on the Structure and the Wetting Angle Values of Silica Coatings

Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1058
Author(s):  
Anna Adamczyk
Keyword(s):  
Porous Materials ◽  
Protective Coatings ◽  
Deposition Process ◽  
Dip Coating ◽  
Wetting Angle ◽  
Properties Of Coatings ◽  
Metallic Substrates ◽  
Silica Coatings ◽  
Silica Precursor ◽  
Silica Sols

The surrounding environment often acts in a destructive way on materials we apply in our everyday life. The best way to protect them against such activity is to cover the basic materials with coatings possessing different properties, tailored to their applications. Anticorrosive layers are one of the biggest groups of such protective coatings, especially those containing silica or its derivatives. Depending on a type of silica precursor and a method of deposition, one can obtain coatings of different structures and properties. In this work, three different silica precursors were applied: TEOS (tetraethylorthosilane), DDS (dimethyldiethoxysilane) and AerosilTM (the powder silica). Sols of different concentrations of the aforementioned precursors as well as commercially available preparations (Sarsil H1 4/2 and SILOXAN W290) were applied for thin films deposition by a dip coating or an infiltration method. The substrates could be divided in two groups: metallic (steel and titanium or titanium alloys) and porous (represented by old brick, sandstone and limestone). Following the deposition process, the layers on metallic substrates were additionally annealed at 500 °C to improve their adhesion and mechanical properties, while those on porous materials were dried in air. All prepared coatings were primarily studied by FTIR spectroscopy and X-ray diffraction. The morphology of their surfaces was imaged by SEM and AFM microscopies, which also allowed determination of the roughness of obtained materials. The measurements of wetting angle values enabled to find the relationship between the surface topography, the type of silica precursor and the hydrophobic/hydrophilic properties of the samples. The results confirmed the hydrophobic properties of coatings obtained by the infiltration technique on the porous materials and the high hydrophilicity of the annealed thin film deposited on the metallic substrates.

Development of deposition process of cerium-containing protective coatings on alloyed steel

2019 ◽  
pp. 38-42
Author(s):  
A.A. Abrashov ◽  
◽  
N.S. Grigoryan ◽  
T.A. Vagramyan ◽  
A.F. Zhukov ◽  
...  
Keyword(s):  
Protective Coatings ◽  
Deposition Process ◽  
Alloyed Steel

scholarly journals Graphene Deposition on Glass Fibers by Triboelectrification

2021 ◽  
Vol 11 (7) ◽  
pp. 3123
Author(s):  
Haroon Mahmood ◽  
Laura Simonini ◽  
Andrea Dorigato ◽  
Alessandro Pegoretti
Keyword(s):  
Graphene Oxide ◽  
Interfacial Shear Strength ◽  
Glass Fibers ◽  
Deposition Process ◽  
Solution Concentration ◽  
Dip Coating ◽  
Slight Improvement ◽  
Reduced Graphene ◽  
Fiber Matrix ◽  
Positively Charged

In this work, a novel nanomaterial deposition technique involving the triboelectrification (TE) of glass fibers (GF) to create attractive charges on their surface was investigated. Through TE, continuous GF were positively charged thus, attracting negatively charged graphene oxide (GO) nanoparticles dispersed in a solution. The electrical charges on the glass fibers surface increased with the intensity of the TE process. The deposited GO coating was then chemically treated to obtain reduced graphene oxide (rGO) on the surface of GFs. The amount of coating obtained increased with the GO solution concentration used during the deposition process, as revealed by FESEM analysis. However, the same increment could not be noticed as a function of the intensity of the process. Both uncoated and coated GF were used to obtain single fiber microcomposites by using a bicomponent epoxy matrix. The fiber/matrix interfacial shear strength was evaluated through micro debonding tests, which revealed an increment of fiber/matrix adhesion up to 45% for rGO coated GF in comparison to the uncoated ones. A slight improvement in the electrical conductivity of rGO coated fibers through TE compared to conventional dip coating was also observed in terms of volumetric resistivity by a four-point probe setup.

scholarly journals Mechanical Properties of Protective Coatings against Marine Fouling: A Review

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 173
Author(s):  
Alessandro Pistone ◽  
Cristina Scolaro ◽  
Annamaria Visco
Keyword(s):  
Mechanical Properties ◽  
Large Scale ◽  
Protective Coatings ◽  
Scale Up ◽  
Product Distribution ◽  
Properties Of Coatings ◽  
Fouling Organism ◽  
Ship Hulls ◽  
Marine Industry ◽  
Application Fields

The accumulation of marine organisms on ship hulls, such as microorganisms, barnacles, and seaweeds, represents a global problem for maritime industries, with both economic and environmental costs. The use of biocide-containing paints poses a serious threat to marine ecosystems, affecting both target and non-target organisms driving science and technology towards non-biocidal solutions based on physico-chemical and materials properties of coatings. The review reports recent development of hydrophobic protective coatings in terms of mechanical properties, correlated with the wet ability features. The attention is focused mainly on coatings based on siloxane and epoxy resin due to the wide application fields of such systems in the marine industry. Polyurethane and other systems have been considered as well. These coatings for anti-fouling applications needs to be both long-term mechanically stable, perfectly adherent with the metallic/composite substrate, and capable to detach/destroy the fouling organism. Prospects should focus on developing even “greener” antifouling coatings solutions. These coatings should also be readily addressable to industrial scale-up for large-scale product distribution, possibly at a reasonable cost.

scholarly journals Modification of water-suspension epoxy varnish and paint materials by nanostructured magnesium oxide

2020 ◽  
Vol 56 (1) ◽  
pp. 105-113
Author(s):  
V. V. Komar ◽  
T. A. Poсhodina ◽  
N. V. Kulinich ◽  
N. P. Krutko ◽  
L. V. .Ovseenko
Keyword(s):  
Magnesium Oxide ◽  
Protective Coatings ◽  
Curing Temperature ◽  
Aggregative Stability ◽  
Functional Surface ◽  
Properties Of Coatings ◽  
Mechanical Dispersion ◽  
Bead Mill ◽  
Powder Suspension ◽  
Size Of Particles

The process of modifying aqueous powder suspension materials (APS) based on solid epoxy film-forming agents with highly dispersed powders of magnesium oxide was studied: production by ChemPur (n-MgO – primary size of particles is 36 nm), and magnesium oxide synthesized by a template method from the concentrated bischofite solution (MgOlab – primary size of particles is 102.8 nm). It was shown that presence of active functional surface OHgroups in both samples of magnesium oxide leads to the formation of secondary structures: aggregates and agglomerates. The nature of the influence of the size of aggregates of MgO particles and the conditions of dispersion on the properties of protective coatings is established. The nature of the influence of particle size and dispersion conditions on the properties of protective coatings is established. Optimal properties of coatings based on APS, sedimentation and aggregative stability of suspensions are implemented only under the condition of effective mechanical dispersion in a bead mill, when the most intensive destruction of large aggregates of n-MgO up to 50–60 nm occurs. The distribution of nanoparticle agglomerates in APS at the micro level (700–800 nm) using the MgO-lab does not lead to a significant change in the properties of APS and coatings based on them.It is shown that the introduction of n-MgO into APS allows reduces the curing temperature of the coatings from 110 to 90–100 °С. It is caused by the increase in the density of cross-linking of the spatial structure of polymer. The strength of modified coatings upon impact and tension increases by 2 times in comparison with the base composition, which does not contain nanomodifier, during curing of coatings at100 °C. In comparison with the known water-borne epoxy paints and varnishes, APS compositions are one-pack, they are more technological in use, have a long lifetime (up to 12 months in comparison with the viability of known two-pack epoxies, 1-8 hours). Materials can be used in industry for the protection of metal products, both as primers and as independent coatings.

Phases Obtained from Heat Treatment of Mn-Co-Based Coatings Deposited by Dip Coating

2014 ◽  
Vol 798-799 ◽  
pp. 323-327
Author(s):  
A. Bervian ◽  
Matias Angelis Korb ◽  
I.D. Savaris ◽  
G.A. Ludwig ◽  
L.S. Barreto ◽  
...  
Keyword(s):  
Dip Coating ◽  
Solid Oxide ◽  
Spinel Type ◽  
Ferritic Stainless Steels ◽  
Metallic Substrates ◽  
Electrolysis Cells ◽  
Steel Aisi ◽  
Solid Oxide Electrolysis Cells ◽  
Dip Coating Technique ◽  
Aisi 430

Studies have been performed to improve the oxidation resistance of ferritic stainless steels at high temperatures because these materials have been proposed for the manufacture of interconnectors for solid oxide fuel cell (SOFCs) and solid oxide electrolysis cells (SOECs) operating at intermediate temperatures (IT-SOFCs). Among the coatings employed, ceramic spinel-type oxides have been the most frequently applied. In this context, Mn-Co-based coatings were deposited on ferritic stainless steel (AISI 430) in this study using a dip-coating technique. The obtained coatings were characterized with respect to their morphology by SEM, their elementary composition by EDS and their structure by XRD. It was possible to produce continuous and adherent Mn-Co-based coatings on the surface of the metallic substrates.

APATITIC NANOPOWDERS AND COATINGS: A COMPREHENSIVE REVIEW

2021 ◽  
Author(s):  
RAVINDER PAL SINGH ◽  
UMA BATRA
Keyword(s):  
Sol Gel ◽  
Dip Coating ◽  
Clinical Applications ◽  
Hard Tissue ◽  
Preparation Methods ◽  
Comprehensive Review ◽  
Metallic Substrates ◽  
Surface Modification Techniques ◽  
Dental Applications ◽  
Insight Into

The use of artificial biomaterials has been acclaiming potential therapeutic scope in diverse clinical applications. This review started with the description of the basics of biomaterials, and desirable properties, which are the prerequisites to understand biomaterials. The orthopedic biomaterials, their classification and the importance of calcium phosphate (CaP) materials for hard-tissue applications were utterly discussed. Furthermore, among the various CaP biominerals, the importance of hydroxyapatite (HAP) and its synthesis techniques was comprehensively reviewed. The sol–gel route for the synthesis of HAP nanoparticles and deposition of coatings were systematically studied. Among the metallic substrates, Ti6Al4V alloy remained the focus of this study. Moreover, several film pre-preparation methods were also given due importance. The importance of other surface modification techniques, especially in the context of Ti6Al4V substrates, was also discussed. Among several coating techniques to deposit CaP coatings, special attention was paid to the spin and dip coating techniques. In addition to monolithic HAP coatings, reinforced and antimicrobial HAP coatings were also reviewed from broad perspectives. Therefore, this review provides an in-depth insight into the preparation and properties of apatitic nanoparticles and their coatings for orthopedic and dental applications.

scholarly journals Estimation of anti-icing properties of coatings

2019 ◽  
Vol 135 ◽  
pp. 01009
Author(s):  
Valentina Loganina ◽  
Svetlana Kislitsyna
Keyword(s):  
Initial Period ◽  
Wetting Angle ◽  
Silicone Resin ◽  
Thermal Imager ◽  
Freezing Front ◽  
Properties Of Coatings ◽  
Metal Structures ◽  
Wetting Hysteresis ◽  
Inclined Surface ◽  
Kinetics Of

The proposed composition for anti-icing coating of metal structures. The composition contains as the filler used aerosil brand R 972 with a density of 2360 kg / m3, particle size of 16 nm and a specific surface 12000 m2 / kg. Silicone resin SILRES® MSE 100 with a 10% concentration was used as a binder. The degree of hydrophobicity was estimated by the value of the wetting angle. In order to characterize the anti-icing properties of the coatings, we used the static and dynamic (advancing and retreating) wetting angle, as well as wetting hysteresis, for which we measured the angles of leakage, and the angles of drift from. Studies of the dynamics of freezing drops on the surface were performed using a TESTO 875-1 thermal imager. It is shown, that the hysteresis of wetting of the superhydrophobic surface based on the developed composition is 3.7 degrees. The critical angle of rolling drops of water from an inclined surface is determined. In the study of the kinetics of freezing of a drop of water on a metal surface, an uneven distribution of temperature on the surface of a drop of water is observed. The process of freezing drops is multistage. In the initial period, there is a transfer of heat from the surface to a drop of water. This stage is followed by the process of freezing the drop, which is manifested in the movement of the freezing front from the substrate upwards.

scholarly journals Influencia del tipo de sinterizado en el comportamiento anticorrosivo de recubrimientos sol-gel

Respuestas ◽  
2016 ◽  
Vol 13 (2) ◽  
pp. 5-10
Author(s):  
Jorge Hernando Bautista-Ruiz ◽  
César Armando Ortiz-Otálora ◽  
Enrique Vera-Lopez
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Electrochemical Impedance ◽  
Steel Substrate ◽  
Sol Gel ◽  
Dip Coating ◽  
Sintering Process ◽  
Properties Of Coatings ◽  
Corrosive Attack ◽  
Plasma Sintering

Este trabajo muestra un estudio electroquímico de recubrimientos SiO2 TiO2 ZrO2 obtenidos por el método sol-gel, sinterizados vía plasma y vía convencional. Los recubrimientos se conformaron a partir de Si(OC2H5)4, Ti(OBu)4 y Zr(OC3H7)4, se depositaron sobre sustratos de acero ANSI/304 mediante dip-coating en monocapa y bicapa. El proceso de densificado vía plasma se realizó a temperaturas del sustrato de 250 ºC, 300 ºC y 330 ºC y el convencional a 400 ºC y a una velocidad de calentamiento de 2 ºC/min. El comportamiento anticorrosivo se estudió mediante las técnicas de espectroscopía de impedancia electroquímica (EIS) y Tafel. Se observó que el proceso de sinterización vía plasma, mejora la resistencia a la corrosión con respecto al método convencional.Palabras Clave: sol-gel; corrosión; plasma; EIS;Tafel Abstract This work shows a comparative electrochemical study among the anticorrosive properties of coatings SiO2 TiO2 ZrO2 obtained by the method sol-gel and plasma sintering process and conventional. The coatings conformed to starting from Si(OC2 H5 )4 , Ti(OBu)4 and Zr(OC3 H7 )4 . These were deposited on steel substrate 304 by means of dip-coating in mono-layer and bi-layer. The plasma sintering process was carried out to temperatures of the substrate of 250 ºC, 300 ºC and 330 ºC and the conventional to 400 ºC and a speed of heating of 2 ºC/min. the anticorrosive behavior was studied by means of the techniques of electrochemical impedance spectroscopy (EIS) and Tafel. It was observed that the plasma sintering process, it improves the resistance to the corrosive attack to in regard to the conventional method.Keywords: sol-gel, corrosion, plasma, EIS, Tafel

Properties of Antireflective Nanoporous Silica Coatings on Silicate Glass Depending on the Rate of the Dip Coating

2020 ◽  
Vol 46 (3) ◽  
pp. 260-266
Author(s):  
B. B. Troitskii ◽  
A. A. Lokteva ◽  
M. A. Novikova ◽  
M. A. Lopatin
Keyword(s):  
Silicate Glass ◽  
Dip Coating ◽  
Nanoporous Silica ◽  
Silica Coatings

Influence of Aluminide Layer on the Dynamics of the Development of Fatigue Damage in Ni-Cr-Co Alloy

2015 ◽  
Vol 240 ◽  
pp. 101-107
Author(s):  
Dominik Kukla ◽  
Ryszard Sitek
Keyword(s):  
Protective Coatings ◽  
Chemical Deposition ◽  
Deposition Process ◽  
Damage Parameter ◽  
Damage Development ◽  
Near Surface ◽  
Surface Areas ◽  
Number Of Cycles ◽  
Aluminide Layer

Thermomechanical conditions in which the elements of modern aircraft engines work, require the use of protective coatings. The coatings increase the creep strength and also the local thermal stress in the near-surface areas due to the differing thermal expansion of particular material layers. For this reason it is necessary to develop a method for evaluating the operating properties of nickel superalloys with the aluminide layer, taking into consideration the surface processes related to the thermo-mechanical fatigue, taking place during the operation. In the presented work the assessment of the influence of the aluminium-coated layer, deposited on the nickel alloy specimens in the chemical deposition process (CVD) on the changes of the damage parameter in cyclic load conditions was carried out. The damage parameter was defined as a total strain in consecutive load cycles. The dynamics of damage development was analysed for two specimen lots (4 with the layer and 4 without it) displaying axial symmetry with a narrowing in the measured section. The results obtained were correlated with the results of fractography studies using SEM. The results obtained were used for the determination of the relationship between the damage parameter being the sum of the average strain and the strain amplitude, and the number of cycles, until the specimen is destroyed.

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