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Number of results: 89
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Abstract

Sol-gel derived silica possess many promising features, including low-temperature preparation procedure, porosity, chemical and physical stability. Applications exploiting porous materials to encapsulate sensor molecules, enzymes and many other compounds, are developing rapidly. In this paper some potential applications, with emphasis on biomedical and environmental ones, are reviewed. The material preparation procedure is described and practical remarks on silica-based sol-gels are included. It is reported that sol-gels with entrapped various molecules may be used in construction of implants and coatings with bioactive properties. It is shown how to exploit the sol-gel production route for construction of sol-gel coated fiberoptic applicators for lasertherapy. The applications of bioactive materials are discussed, as well. It is demonstrated that it is possible to immobilize photosensitive compounds in sol-gel matrix without loosing their photoactivity. Some examples of sol-gel based biosensors are demonstrated, as well, showing their potential for detecting various gases, toxic substances, acidity, humidity, enzymes and biologically active agents.

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Authors and Affiliations

H. Podbielska
A. Ulatowska-Jarża
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Abstract

Results of scientific researches show the trend of active using nitrides and borides of transition

metals and their combination in developing protective materials. While single elements

nitrides have been well studied, their multilayer modifications and combinations require

more detailed study. Physical-mechanical properties and structural-phase state of multilayer

coating according to the deposition conditions is an important task for the study.

It will be the analysis of physical-mechanical and electrical properties of coatings based on

refractory metals nitrides, their structure and phase composition and surface morphology

depending on the parameters of condensation. It was established the structure and behavior

of nano scale coatings based on refractory metals nitrides (Ti, Zr) depending on the size

of nano grains, texture, stress occurring in coatings.

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Authors and Affiliations

Anton Panda
Konstiantyn Dyadyura
Tatyana Hovorun
Oleksandr Pylypenko
Marina Dunaeva
Iveta Pandova
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Abstract

The article presents the results of permeability measurements of a zirconium alcohol coating applied on moulds and cores. The introduction extensively discusses the reasons for the application of protective coatings, as well as their advantages and disadvantages. Also, the problems related to the application of protective coatings are presented i.e. limited permeability and thus the possibility of the presence of gas-originated defects in the casts. Next, the paper discusses the methods of measuring the permeability of protective coating proposed by Falęcki and Pacyniak. The study also presents an indirect permeability measurement method. For the investigations, zirconium alcohol coatings with the three conventional viscosities 10, 20 and 30s were used. The viscosity was determined by means of the Ford cup with the clearance of 4mm. The coatings were applied onto profiles of Φ 50 x 50 mm, made of moulding sand consisting of a sand matrix with the mean grain size of dL = 0,11, 17, 24, 31 and 34 mm and phenol-formaldehyde resin. The effect of the matrix grain size on the permeability of the sand with and without a coating was determined.

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Authors and Affiliations

Ł. Jamrozowicz
ORCID: ORCID
A. Siatko
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Abstract

This investigation was undertaken to determine the optimum conditions for physical-chemical treatment of waste water contaminated with heavy metals in the industry of metallic coatings. The industry uses substances such as: inorganic acids, alkalis, acidic and alkaline metal salts, that has a high water demand in the processes of flushing and cleaning the parts to be coated. According to the preliminary characterization of samples and reported in the literature theory, physico-chemical process was implemented for the removal of contaminants that consisted in chemical oxidation of CN-ions, followed by chemical precipitation made next to a coagulation/flocculation and subsequent adsorption on activated coal. Laboratory scale tests showed the optimal conditions of treatment including chemical oxidation by the addition of 4.15 cm3 of H2O2(30%) per gram of CN, chemical precipitation with NaOH to a pH of 12, followed by coagulation/flocculation with Fe2(SO4)3 at a speed of 135 rpm for 3 min and 20 rpm for 20 min and finally the addition of 1.0 g of adsorbent previously activated at 700°C. From this study, it is clear that the adsorption on activated carbon is highly efficient in the removal ofheavy metals from industrial waste water from electroplating. However, it is also clear that the parallel application of the treatments, shown here, is more effective to completely remove contaminants such as lead, nickel, silver, and copper at la-boratory scale, so it is recommended the simultaneous use of these physico-chemical processes.

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Authors and Affiliations

Jacipt A.R. Valencia
Jordi P. González
Iris Jimenez-Pitre
Geomar Molina-Bolívar
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Abstract

The paper presents the results of research studies involving the ceramic-metal tool materials with the deposited nitride coatings on the basis of aluminium, titanium and silicon. The cathodic arc evaporation with lateral rotating cathodes method was used for deposition of nanocrystalline, wear resistant nitride coatings – AlTiSiN type. Structural examinations are presented of the applied coatings and their support material made on the scanning electron microscope (SEM) and the scanning/transmission electron microscope (STEM). Chemical composition analysis as a function of the distance from the specimen surface, the so-called profile analysis, were carried out also. The structural analysis confirms that deposited multilayer coatings have dense microstructure without any visible porosity and delamination. It was found that the investigated coatings have nanocrystalline structure and consisting of fine crystallites even less than 6nm. Lattice deformations and numerous structural defects were also observed in the nanolayers. Depositing the AlTiSiN coatings results in the significant hardness increase within the range of 2252 ±256 to 2908 ±295 HV0.01.
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Authors and Affiliations

A.E. Tomiczek
K. Gołombek
K. Matus
D. Pakuła
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Abstract

Optical Coherence Tomography (OCT) is one of the most rapidly advancing techniques. This method is capable of non-contact and non-destructive investigation of the inner structure of a broad range of materials. Compared with other methods which belong to the NDE/NDT group (Non-Destructive Evaluation/Non-Destructive Testing methods), OCT is capable of a broad range of scattering material structure visualization. Such a non-invasive and versatile method is very demanded by the industry. The authors applied the OCT method to examine the corrosion process in metal samples coated by polymer films. The main aim of the research was the evaluation of the anti-corrosion protective coatings using the OCT method. The tested samples were exposed to a harsh environment. The OCT measurements have been taken at different stages of the samples degradation. The research and tests results have been presented, as well as a brief discussion has been carried out.

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Authors and Affiliations

Paulina Antoniuk
Marcin Strąkowski
Jerzy Pluciński
Bogdan Kosmowski
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Abstract

This article presents measurements of the thickness of alcohol-based coatings on sand foundry cores and moulds. These coatings were applied using two methods, the dipping method and the painting method. For the purposes of the study, a zircon alcohol-based coating was prepared with three different levels of nominal viscosity; very thin at 10s, average at 20s, and thick at 30s. The coating was applied to a core made of quartz sand and furan resin. The cores were made of sand with three different grain sizes; dL = 0.22 mm – fine sand, dL = 0.33 mm medium sand, and dL = 0.47 mm coarse sand. In the study, the thickness of the coating obtained to the core was measured immediately after application as well as after drying. Additionally, the extent of penetration into the intergranular spaces of the core matrix was measured. On the basis of this study, the impact of the grain size of the core matrix on the thickness of the coating and its penetration into the core was assessed. The thickness of coatings obtained using different application methods was also assessed.

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Authors and Affiliations

Ł. Jamrozowicz
J. Kolczyk-Tylka
A. Siatko
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Abstract

This paper presents the study of microstructure and properties of 8 mol% yttrium stabilized zirconia coating fabricated by Plasma Spray Physical Vapor Deposition technique on commercial pure titanium. The coating was characterized by X-ray diffraction, high resolution scanning electron microscope, profilometer, nanoindentation and nanomachining tests. The X-ray phase analysis exhibit the tetragonal Zr0.935Y0.065O1.968, TiO and α-Ti phases. The Rietveld refinement technique were indicated the changes of crystal structure of the produced coatings. The characteristic structure of columns were observed in High Resolutions Scanning Electron Microscopy. Moreover, the obtained coating had various development of surfaces, thickness was equal to 3.1(1) µm and roughness 0.40(7) µm. Furthermore, the production coatings did not show microcracks, delamination and crumbing. The performed experiment encourages carried out us to tests for osseointegration.

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Authors and Affiliations

J. Barczyk
G. Dercz
I. Matuła
M. Góral
J. Maszybrocka
D. Bochenek
W. Gurdziel
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Abstract

Presented are results of a preliminary research on determining a possibility to use microwave radiation for drying casting protective

coatings applied on patterns used in the lost foam technology. Taken were measurements of permittivity εr and loss factor tgδ at 2.45 GHz,

as well as attempts were made of microwave drying of a protective coating based on aluminium silicates, applied on shapes of foamed

polystyrene and rigid polymeric foam. Time and results of microwave drying were compared with the results obtained by drying at 50 °C

by the traditional method commonly used for removing water from protective coatings. Analysis of the obtained drying kinetics curves

demonstrated that selection of proper operation parameters of microwave equipment permits the drying time to be significantly shortened.

Depending on kind of the pattern material, drying process of a protective coating runs in a different way, resulting in obtaining different

quality of the dried coating.

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Authors and Affiliations

B. Opyd
K. Granat
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Abstract

Abstract A conductive boron-doped diamond (BDD) grown on a fused silica/quartz has been investigated. Diamond thin films were deposited by the microwave plasma enhanced chemical vapor deposition (MW PECVD). The main parameters of the BDD synthesis, i.e. the methane admixture and the substrate temperature were investigated in detail. Preliminary studies of optical properties were performed to qualify an optimal CVD synthesis and film parameters for optical sensing applications. The SEM micro-images showed the homogenous, continuous and polycrystalline surface morphology; the mean grain size was within the range of 100-250 nm. The fabricated conductive boron-doped diamond thin films displayed the resistivity below 500 mOhm cm-1 and the transmittance over 50% in the VIS-NIR wavelength range. The studies of optical constants were performed using the spectroscopic ellipsometry for the wavelength range between 260 and 820 nm. A detailed error analysis of the ellipsometric system and optical modelling estimation has been provided. The refractive index values at the 550 nm wavelength were high and varied between 2.24 and 2.35 depending on the percentage content of methane and the temperature of deposition.

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Authors and Affiliations

Robert Bogdanowicz
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Abstract

Mechanical components and tools in modern industry are facing increasing performance requirements leading to the growing need for advanced materials and thus, for modern frictional systems. In the last decades, the Pulsed Laser Deposition (PLD) has emerged as an unique tool to grow high quality mono- as well as multilayers surfaces in metallic/ceramic systems. Building up a knowledge base of tribological properties of industrially-scaled, room temperature deposited PLD hard coatings are the most important step for the application of these coatings in engineering design. Although single-layer coatings find a range of applications, there are an increasing number of applications where the properties of a single material are not sufficient. One way to surmount this problem is to use a multilayer coating. Application of metallic interlayers improves adhesion of nitride hard layer in multilayer systems, which has been used in PVD processes for many years, however, the PLD technique gives new possibilities to produce system comprising many bilayers at room temperature. Tribological coatings consisted of 2, 4 and 16 bilayers of Cr/CrN and Ti/TiN type were fabricated with the Pulsed Laser Deposition (PLD) technique in the presented work. It is found in transmission electron examinations on thin foils prepared from cross-section that both nitride-based multilayer structures studied are characterized by small columnar crystallite sizes and high defect density, what might rise their hardness but compromise coating adhesion. The intermediate metallic layers contained larger sized and less defective columnar structure compared to the nitride layers, which should improve the coatings toughness. Switching from single layer to multi-layer metal/nitride composition improved resistance to delamination.

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Authors and Affiliations

J.M. Lackner
W. Waldhauser
L. Major
J. Morgiel
M. Kot
B. Major
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Abstract

Boron nitride thin layers were produced by means of the pulsed laser deposition technique from hexagonal boron nitride target. Two types of laser i.e. Nd:YAG with Q-switch as well as KrF coupled with RF generator were used. Influence of deposition parameters on surface morphology, phase composition as well as mechanical properties is discussed. Results obtained using Fourier Transformed Infrared Spectroscopy, Transmission and Scanning Electron Microscopy, Atomic Force Microscopy are presented. Micromechanical properties measured during microindentation, scratch and wear tests are also shown.

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Authors and Affiliations

B. Major
W. Mróz
M. Jelinek
R. Kosydar
M. Kot
Ł. Major
S. Burdyńska
R. Kustosz
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Abstract

The paper presents the results of the electrodeposition of nickel composite coatings reinforced with the ceramic SiC particles. A Watts type galvanic bath modified with various organic additives was used. These additives were: 2-sulfobenzoic acid imide (LSA), dioctyl sulfosuccinate sodium salt (DSS), sodium dodecyl sulfate (SDS), tris (hydroxymethyl) aminomethane (THAM) and hexamethyldisilizane (HMDS). The nickel composite coating was electrodeposited on a 2xxx aluminum alloy series substrate (EN-AW 2017) with zinc interlayer. Studies concerned the effect of the applied organic additives on properties of composite coatings such as: microstructure, microhardness, adhesion to the substrate, corrosion resistance and roughness. The structure of the coatings was assessed by scanning electron microscopy and light microscopy. Based on the studies of zeta potential it was found that the bath modification had a significant impact on the amount of the ceramic phase embedded in metal matrix. The tests conducted in a model 0.01 M KCl solution were not fully representative of the true behavior of particles in a Watts bath.

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Authors and Affiliations

M. Nowak
J. Mizera
A. Kłyszewski
A. Dobkowska
S. Boczkal
ORCID: ORCID
A. Kozik
P. Koprowski
ORCID: ORCID
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Abstract

The mechanism in which the coatings made by thermal spraying adhere to the substrate is in most cases of a mechanical nature, thus being dependent on the morphology of the substrate surface. This paper study how the texture of the substrate influences the behavior of dry sliding wear, a behavior based on the adhesion to the substrate of the analyzed coatings. For this purpose, a Co – base powder, was chosen for atmospheric plasma spraying. For the substrate, a rectangular profile made of low-alloy steel was chosen, the surface of which was textured by mechanical abrasion, in order to obtain different degrees of roughness: sample S1 – Ra1 = 1.59 µm, sample S2 – Ra2 = 2.32 µm, sample 3 – Ra3.1 = 1.25 μm, Ra3.2 = 3.88 μm. In the case of sample 3, the texturing was done on one direction, with an elongated profile, so that the effect of the main direction of dry sliding wear on the quality of the coating could be studied. The tests were performed on an Amsler test machine, at constant load, for 1 hour. The samples were mounted in a fixed position, and the wear occurred on the basis of the rotation of the metal disc, without lubrication. It was found that the coating of sample 1 was the most affected, resulting even a partial delamination, and the best behavior was recorded in the case of sample 3.1.
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Authors and Affiliations

D. Cristisor
1
ORCID: ORCID
D.L. Chicet
2
ORCID: ORCID
C. Cirlan Paleu
1
ORCID: ORCID
C. Stescu
1
ORCID: ORCID
C. Munteanu
1 3
ORCID: ORCID

  1. Gheorghe Asachi Technical University of Iasi, Department of Mechanical Engineering, Blvd. Mangeron, No. 61, 700050, Iasi, Romania
  2. Gheorghe Asachi Technical University of Iasi, Department of Materials Science and Engineering, Blvd. Mangeron, No. 41, 700050, Iasi, Romania
  3. Technical Sciences Academy of Romania, 26 Dacia Blvd, Bucharest, 030167, Romania
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Abstract

In this study, energetic behaviors of polyvinylidene fluoride (PVDF)-coated zirconium (Zr) powders were investigated using thermogravimetric analyzer-differential scanning calorimetry (TGA-DSC). PVDF-coated Zr powder had 1.5 times higher heat flow than ZrO2-passivated Zr powder. PVDF-coated Zr powder had a Zr-F compound formed on its surface by its strong chemical bond. This compound acted as an oxidation-protecting layer, providing an efficient combustion path to inner pure Zr particle while thermal oxidation was progressing at the same time. PVDF coating layers also made thermal reaction start at a lower temperature than ZrO2-passivated Zr powder. It was obtained that the surface PVDF coating layer evaporated at approximately 673 K, but the surface oxide layer fully reacted at approximately 923 K by DSC analysis. Hence, Zr powders showed enhanced energetic properties by the PVDF-coated process.
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Bibliography

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[8] J . Dai, D.M. Sullivan, M.L. Bruening, Ind. Eng. Chem. Res. 39, 3528-3535 (2000).
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[11] C.E. Bunker, M.J. Smith, K.A. Shiral Fernando, B.A. Harruff, W.K. Lewis, J.R. Gord, E.A. Guliants, D.K. Phelps, ACS Appl. Mater. Interfaces 2, 11-14 (2010).
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[13] D. Dambournet, A. Demourgues, C. Martineau, S. Pechev, J. Lhoste, J. Majimel, A. Vimont, J.C. Lavalley, C. Legein, J.Y. Buzaré, F. Fayon, A. Tressaud, Chem. Mater. 20, 1459-1469 (2008).
[14] J . McCollum, M.L. Pantoya, S.T. Iacono, ACS Appl. Mater. Interfaces 7, 18742-18749 (2015).
[15] D.T. Osborne, M.L. Pantoya, Combust. Sci. Technol. 179, 1467- 1480 (2007).
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Authors and Affiliations

Won Young Heo
1
ORCID: ORCID
Sung Hwa Bae
2
ORCID: ORCID
Injoon Son
1
ORCID: ORCID

  1. Kyungpook National University, Department of Materials Science and Metallurgical Engineering, Daegu 41566, Republic of Korea
  2. Kyushu University, Department of Materials Process Engineering, Graduate School of Engineering, Fukuoka, Japan
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Abstract

This paper presents the results of research of Ni/diamond composite coatings produced by electrochemical reduction method. Research was focused on composite coatings with nickel matrix and diamond as a disperse phase and for comparison purposes on nanocrystalline nickel coatings. Ni/diamond composite coatings were produced in baths with different content of nanodiamond powder. The structures of the dispersed phase and the composite coatings were analysed by using X-ray diffraction, scanning electron microscopy and light microscopy. Measurements of selected properties of the coatings were performed, including roughness, microhardness, adhesion and abrasive wear resistance. The research results indicate that the produced coatings have a compact structure and good adherence to steel substrate. Moreover, nanocrystalline Ni/diamond composite coatings exhibit greater hardness and reduced abrasive wear resistance compared to nanocrystalline nickel coatings.

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Authors and Affiliations

A. Mazurek
M. Trzaska
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Abstract

Underwater steel structures require periodic maintenance. In the case of vessels, anti-corrosion works are carried out in the shipyard, where very good conditions for applying organic protective coatings can be provided. Very good surface preparation can be obtained by the use of abrasive blasting. The well-prepared metal surface is free from impurities (particularly inorganic salts). Suitable conditions for the application and renovation of coatings are also ensured (creating appropriate climatic conditions, drying the air, setting the appropriate air temperature). However, there are underwater constructions that cannot be transferred above the water level and, therefore, their conservation against corrosion can take place only under the surface of the water, which significantly hinders the execution of renovation works. In this work, protective coatings for underwater application were tested. The application of coatings on selected steel surfaces over and under the water was carried out. Physico-mechanical and electrochemical tests were carried out in order to assess the quality of the obtained corrosion protection. The possible difficulties faced when applying coatings in marine conditions were discussed.

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Authors and Affiliations

J. Orlikowski
A. Jażdżewska
K. Jurak
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Abstract

The objective of the investigation was to identify surface roughness after turning with wedges of coated sintered carbide. The investigation included predicting the average surface roughness in the dry machining of Duplex Stainless Steel (DSS) and the determination of load curves together with roughness profiles for various cutting conditions. The load curves and roughness profiles for various cutting wedges and variable cutting parameters were compared. It has been shown that dry cutting leads to a decrease in friction for lubricated surfaces, providing a small initial contact area where the surface is contacted. The study has been performed within a production facility during the production of electric motor parts and deep-well pumps.

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Authors and Affiliations

Grzegorz M. Królczyk
Stanisław Legutko
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Abstract

Room temperature vulcanized (RTV) silicone rubber is widely used to prevent pollution flashover with its excellent hydrophobicity and hydrophobicity transfer. However, RTV coatings are at the risk of deterioration and failure in heavily polluted operating environment. In this paper, RTV coated insulators with different suspension heights operating in coal ash polluted areaswere sampled. Pollution degree, pollution composition and aging degree of coatings were tested. The result shows that the insoluble pollution contains Al(OH)3 filler precipitated from RTV coating, which indicates the aging of the RTV coating. The top surface coating is more affected by ultraviolet and rainwater than the bottom surface resulting in more serious degradation. As the pollution degree of the lower phase insulator is heavier than that of the upper phase insulator, the erosion effect of pollution on the RTV coating is more intense. The fillers and rubber molecules of RTV continuously precipitate into the pollution layer, leading to further aging. Therefore, the overall aging degree of the lower insulator coating is more serious than that of the upper insulator coating.

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Authors and Affiliations

Lei Lan
Lin Mu
Yu Wang
ORCID: ORCID
Xiaoqing Yuan
Wei Wang
ORCID: ORCID
Zhenghui Li
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Abstract

In article a two-dimensional photonic crystal (PhC) is considered and modelled as a new generation antireflection coating for optoelectronic devices. Traditional antireflective coatings (ARCs) reduce the reflection of the radiation only – the new generation of antireflective coatings should affect the distribution of the radiation also. Such functionality can be provided by the two-dimensional PhC which reduce the reflection and scatter transmitted light. Prior to the fabrication, the PhCs should be designed and analysed. Results of the analysis should provide quantitative means for choice of materials and design solutions. In work, we analyse the electromagnetic field distribution as Poynting vectors inside the materials of optoelectronic devices, in order to investigate the possibility of improving the construction of future optoelectronic devices. Furthermore, we calculate the reflection and transmission of that ARC. It’s a complex optic analysis of new generation of ARC. The numerical analysis has been performed with the FDTD method in Lumerical Software. In work, we consider the two-dimensional photonic crystal on the top surface of optoelectronic structures. We compared the results with the traditional ARC from these same parameters as PhC: thickness and material. As an example, we presented the application of modelled, photonic crystal, thin-film, GaAs solar cells with PhC on top. The efficiency of this solar cell, using the photonic crystal, was improved by 6.3% over the efficiency of this same solar cell without PhC. Thus, our research strongly suggests that the unique properties of the photonic crystal could be used as a new generation of ARC.

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Authors and Affiliations

D. Przybylski
S. Patela
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Abstract

To obtain anti-corrosive thermo-diffusion zinc coatings, the authors use highly effective zinc saturating mixtures. This technology makes it possible to obtain coatings with a high zinc content in the δ-phase as well as a zinc-rich phase of FeZn13 (ζ-phase) on the coating surface. As a result of long-term studies into the corrosion properties of thermo-diffusion zinc (TDZ) coatings conducted by the authors, a number of features of their corrosive behavior have been established. The corrosion rate of those coatings in desalted and chloride-containing media is lower than those of galvanic or hot-dip zinc coatings. The corrosion behavior depends on the content of zinc on the surface and the texture features of the coating. The results showed that on the surface of thermo-diffusion coatings in the corrosion on media containing chloride ions, zinc hydroxychloride (simonkolleite – Zn5Cl2[OH]8[H2O]) has been formed. Compared to coatings obtained by other methods, the rate of simonkolleite formation was higher on TDZ coatings, which might have a positive effect on their resistance in aggressive atmospheres.

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Authors and Affiliations

A. Biryukov
R. Galin
D. Zakharyevich
A. Wassilkowska
A. Kolesnikov
T. Batmanova
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Abstract

Ni625/WC composite coatings added with different amounts of Y 2O 3were prepared on the surface of 304 stainless steels by laser cladding. This study focused on the microstructure characteristics, microhardness, and corrosion performances of Ni625/WC composite coatings. The results showed that Y 2O 3 can effectively improve the corrosion resistance of the composite coatings. The microstructure from the bottom to the surface of composite coatings consists of plane crystal, cellular crystal, columnar crystal and equiaxed crystal. The Y 2O 3content of optimum composite coating was 1.0%. Its microhardness was three times that of matrix material. In addition, the corrosion current density of the composite coating was only 2% of Ni625/WC coating, which was attributed to the good properties of Y 2O 3 and appropriate Y 2O 3 refined microstructure.
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Authors and Affiliations

Jinling Yu
1
ORCID: ORCID
Zheng Zhentai
1
ORCID: ORCID
Shuai Li
1
ORCID: ORCID
Donghui Guo
1
ORCID: ORCID
Liang Chang
1
ORCID: ORCID

  1. Hebei University of Technology, School of Materials Science and Engineering, No. 5340, Xipingdao Road, Beichen District, Tianjin, 300401, PR China
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Abstract

Electrochemical Cr coatings doped with diamond nanoparticles were deposited on sintered steels with different carbon contents (0.2-0.8 wt.-%). The mechanical properties of surfaces as hardness and wear resistance increase as compared to the steel substrate. Microcutting and microgridding mechanisms were observed after tribological tests, but also adhesive wear in some areas was observed. X-ray examination indicated that the layer was textured, with the exception of the sample with the highest concentration of diamond nanoparticles in the electrolyte (42 g/l). The intensity ratio ICr110/ICr200 was calculated and compared with the indices for a standard sample. The greatest differences in the intensity ratio occurred for the samples with low carbon content (0.2%C). On the other hand, more the material is textured the greater the difference.

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Authors and Affiliations

V. Petkov
R. Valov
M. Witkowska
M. Madej
G. Cempura
M. Sułowski

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