scholarly journals Protective Coatings for Medieval Stained Glasses

1990 ◽  
Vol 185 ◽  
Author(s):  
H. Schmidt ◽  
D. Fuchs
Keyword(s):  
Surface Modification ◽  
Protective Effect ◽  
Protective Coatings ◽  
Ceramic Coatings ◽  
Effective Protection ◽  
Long Period ◽  
Organically Modified ◽  
Additional Protection ◽  
Glass Surfaces ◽  
Molecular Layers

AbstractThe corrosion protective effect of the surface modification of corrosion sensitive glass surfaces and of ORMOCER (= organically modified ceramic) coatings is investigated. The surface modification provides a modest protection, perhaps useful for additional protection in combination with external glazing. The advantage is the “invisability” of the modification due to the thickness of several molecular layers. An effective protection can be obtained by a diffusion barrier pigmented ORMOCER coatings. First outdoor results on medieval glasses are very hopeful, but long period experience is necessary for wider application.

scholarly journals Radon retrospective dosimetry in different environments

2020 ◽  
Vol 27 ◽  
pp. 77
Author(s):  
I. Giaritzoglou ◽  
X. Aslanoglou ◽  
K. C. Stamoulis ◽  
S. Alexandropoulou ◽  
K. G. Ioannides
Keyword(s):  
Lung Cancer ◽  
Alpha Spectrometry ◽  
Conversion Factor ◽  
Residential Buildings ◽  
Long Period ◽  
Retrospective Dosimetry ◽  
Glass Surfaces ◽  
Polonium 210Po

In the present study of retrospective dosimetry, measurements or Radon (222Rn) and Polonium (210Po) were performed. Radon is a radioactive gas and is concentrated in the interior of residential buildings and working places and is considered as a primary cause of lung cancer. To evaluate measurements in different environments, alpha spectrometry was employed in estimating exposure to radon in various locations over a long period of time (hence, the use of the term “retrospective”) through exposure of plastic and glass surfaces. Following these measurements, the Conversion Factor (CF) was calculated. This factor correlates the measured surface concentrations of 210Po with the 222Rn concentrations in the environments under study.

scholarly journals Применение покрытий AlN для защиты поверхности гетероструктур системы AlGaAs/GaAs от взаимодействия с атмосферным кислородом

2020 ◽  
Vol 46 (6) ◽  
pp. 16
Author(s):  
Е.В. Фомин ◽  
А.Д. Бондарев ◽  
И.П. Сошников ◽  
N.B. Bercu ◽  
L. Giraudet ◽  
...  
Keyword(s):  
Protective Coatings ◽  
Residual Pressure ◽  
Aluminum Oxynitride ◽  
Effective Protection ◽  
Pure Nitrogen ◽  
Plasma Sputtering ◽  
Laser Heterostructures ◽  
Ion Plasma ◽  
Thin Aluminum ◽  
Film Substrate

The paper presents the results of the synthesis of thin aluminum nitride films by reactive ion-plasma sputtering and the study of their properties with the aim of using as the protective coatings for the high-power AlxGa1-xAs/GaAs semiconductor laser heterostructures. EDS studies and ellipsometry showed that at a residual pressure in the chamber of the order of ~10-5 Torr, a layer of aluminum oxynitride is formed in the films. In this case, the film-substrate heterointerface can undergo oxidation. However, AlN films with a thickness of the order of 100 nm grown in a pure nitrogen medium with a residual pressure of ~10-7 Torr apparently do not contain oxygen, and can reliably prevent its penetration into the heterointerface region. Potentially, they can serve as effective protection for oxidation sensitive heterostructures.

Wires for Arc and High Velocity Flame Spraying—Wire Design, Materials, and Coating Properties

2000 ◽  
Author(s):  
J. Wilden ◽  
A. Wank ◽  
F. Schreiber
Keyword(s):  
High Velocity ◽  
Protective Coatings ◽  
Large Diameter ◽  
Flame Spraying ◽  
Arc Spraying ◽  
Coating Properties ◽  
Effective Protection ◽  
Low Degree ◽  
High Degree ◽  
Cored Wires

Abstract Cored wires show a high potential for production of protective coatings for combined corrosion and wear applications. Iron and nickel based grooved cored wires without and with different reinforcing carbide fillers have been sprayed by arc- and high velocity combustion wire (HVCW) spraying with a Praxair Type 216 gun. Depending on the wear mechanism coatings with a similar abrasive or oscillating wear resistance like HVOF WC/Co/Cr 86/10/4 have been produced. For effective protection against oscillating wear wires with a large diameter and therefore a high content of reinforcing carbide filler have to be applied. All nickel based coatings with chromium addition show an improved corrosion resistance compared to HVOF-sprayed WC/Co/Cr 86/10/4. For coatings from wires with NiCr 80/20 velum no effect of severe sulphurous corrosion in the DIN 50018 test is observed. HVCW-spraying is especially suitable, when only a low degree of interaction between velum and filler material is wanted as for cermet-like coatings. Conventional arc-spraying rather meets the demands of a high degree of interaction between velum and filler necessary for the production of pure metallic coatings like NiCrBSi. All manufactured coatings show good machinability.

Study on Surface Modification Coating on High-Purity Mg

2015 ◽  
Vol 713-715 ◽  
pp. 2880-2888 ◽  
Author(s):  
Yong Jun Zhang ◽  
Cui Ling Zhao ◽  
Sheng Tao ◽  
Shu Gong Jia ◽  
Zheng Chun Liu
Keyword(s):  
Surface Modification ◽  
High Purity ◽  
Treatment Time ◽  
Formation Rate ◽  
Microarc Oxidation ◽  
Film Coating ◽  
Ceramic Coatings ◽  
Anode Surface ◽  
Layer Depth ◽  
Two Stages

Microarc oxidation (MAO) surface modification course on high-purity Mg at constant DC and the resultant ceramic coatings were investigated. MAO was the course in which the pre-existing film/coating was modified or substituted and strengthened repeatedly. SEM disclosed the inhomogeneous formation rate of ceramic coating in different micro-regions at anode surface during MAO. Three-stage behavior of MAO including pre-microarc discharge stage, transitional stage and then further modifying stage was put forward. The latter two stages proceeded under continuous discharge conditions, accompanied by intensive evolution of gas. EDS analyses indicated that the resultants of MAO consisted mainly of Mg, O and Si elements. XRD analyses revealed the dependence of phase composition on treatment time and coating layer depth.

Ceramic Coatings for High Temperature Service

CORROSION ◽  
1960 ◽  
Vol 16 (7) ◽  
pp. 309t-311t ◽  
Author(s):  
S. W. BRADSTREET
Keyword(s):  
Ceramic Coating ◽  
Protective Coatings ◽  
Ceramic Coatings ◽  
Shear Stresses ◽  
Thermal Gradients ◽  
High Shear ◽  
Thermal Environments ◽  
Potential Value ◽  
Time Periods ◽  
Short Time

Abstract Several types of coatings may be used for service in extreme thermal environments. For moderate temperatures (to about 1700 C) for short time periods, these coatings may be rather simple refractory layers. Under the more severe conditions of ramjet and rocket operation, reinforced materials, graded substrate-coating interfaces, or multilayers are required. Where thermal gradients are severe and where high shear stresses and abrasion exist, composites must be used which utilize controlled ablation. The principles which appear to dominate the attachment of a ceramic coating to a variety of substrates are reviewed, and the deficiencies and advantages of different combinations are discussed. Principles for “tailoring” protective coatings for refractory metals is suggested, and a flame-sprayed ceramic coating of potential value as a combustion catalyst is used to illustrate these principles. 5.4.2

Use of Silicon-Based Coating for High Temperature Protection of Metallic Alloys

2011 ◽  
Vol 696 ◽  
pp. 308-313 ◽  
Author(s):  
J. Xu ◽  
Jérôme Favergeon ◽  
P.E. Mazeran ◽  
Gérard Moulin ◽  
C. Vu
Keyword(s):  
Acoustic Emission ◽  
High Temperature ◽  
Protective Coatings ◽  
Low Carbon Steel ◽  
Metallic Alloys ◽  
Mechanical Resistance ◽  
Low Carbon ◽  
Effective Protection ◽  
Structural Conversion ◽  
Silicon Based

This contribution presents results which show the possibility to develop protective coatings from perhydropolysilazane (PHPS) on low carbon steel. In order to have an effective protection, the pyrolysis conditions should be carefully controlled. Nanoindentation tests allow characterizing the mechanical resistance of the coating after different pyrolysis conditions. The pyrolysis of coated samples has also been monitored by acoustic emission; the results show that the structural conversion of the coating from polymer to ceramics can be detected by acoustic emission.

Synthesis of Multilayer Vacuum Ion-Plasma Coatings Ti-Tin during the Surface Modification

2016 ◽  
Vol 870 ◽  
pp. 113-117 ◽  
Author(s):  
S.R. Shekhtman ◽  
N.A. Sukhova
Keyword(s):  
Surface Modification ◽  
Hollow Cathode ◽  
Technology Development ◽  
Protective Coatings ◽  
Plasma Coating ◽  
Plasma Source ◽  
High Current ◽  
Ion Plasma ◽  
Ionic Bombardment ◽  
High Current Discharge

The article presents the results of the technology development for the vacuum ion-plasma coating deposition with the additional ionic bombardment. As a method to realize the additional ionic bombardment, use of the hollow cathode effect or non-self-maintained high-current discharge generated by the plasma source with an incandescent cathode (PSIC) is suggested. The technology of synthesis of protective coatings with the submicrocrystalline structure was developed.

scholarly journals Cold-Sprayed Aluminum-Silica Composite Coatings Enhance Antiwear/Anticorrosion Performances of AZ31 Magnesium Alloy

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Lijia Fang ◽  
Yuting Xu ◽  
Li Gao ◽  
Xinkun Suo ◽  
Jianguo Gong ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Surface Modification ◽  
Magnesium Alloys ◽  
Cold Spray ◽  
Protective Coatings ◽  
Composite Coatings ◽  
Silica Content ◽  
Protective Layers ◽  
Structural Applications ◽  
Enhanced Surface

Extensive efforts devoted in recent years to booming structural applications of lightweight magnesium alloys are usually undermined by their insufficient surface properties. Surface modification is therefore necessarily required in most cases for enhanced surface integrity of the alloys. Here, we report construction of aluminum-silica protective layers by cold spray on AZ31 magnesium alloys, and the effect of the silica additives on microstructure and mechanical properties of the coatings was examined. The ceramic particles were dispersed evenly in the coatings, and increased silica content gives rise to enhanced adhesion, antiwear performances, and microhardness of the coatings. The even distribution of silica in the coatings altered the wear regimes from adhesive to abrasive wear. The cold spray fabrication of the aluminum-silica protective coatings would facilitate structural applications of the magnesium alloys.

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