Skip Nav Destination
Close Modal
Update search
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
NARROW
Format
Topics
Article Type
Volume Subject Area
Date
Availability
1-20 of 57
Ceramic coating
Close
Follow your search
Access your saved searches in your account
Would you like to receive an alert when new items match your search?
Sort by
Proceedings Papers
ITSC 2021, Thermal Spray 2021: Proceedings from the International Thermal Spray Conference, 315-321, May 24–28, 2021,
Abstract
PDF
Abstract Thermally sprayed ceramic coatings can be used for wear protection as well as thermal and electrical insulation. When exposed to environments with high humidity, the water absorption of the ceramic coating has a tremendous impact on the electrical insulation. In thermally sprayed ceramic coatings, water can easily be absorbed by the porous microstructure of the coating. A general result of the water absorption is the reduction of the dc resistivity. However, in the high frequency regime of ac loads, contrary results were observed for sealed Al 2 O 3 coatings on steel substrates. Specimens exposed to high air humidity have shown an increased ac resistance compared to dry specimens if frequencies above 1 MHz are considered. To analyse this phenomenon, a novel measurement technique was developed to investigate the influence of the water absorption of detached ceramic coatings on the ac resistivity at high frequencies. Moreover, the water absorption of the ceramic is measured gravimetrically. To ensure the results are also applicable to ceramic coatings on substrates, the morphology of the coating was analysed using electron microscopy and compared to reference specimens deposited on steel substrates from [1].
Proceedings Papers
ITSC 2021, Thermal Spray 2021: Proceedings from the International Thermal Spray Conference, 322-330, May 24–28, 2021,
Abstract
PDF
Abstract Thermally sprayed Al 2 O 3 -TiO 2 ceramic coatings provide exceptional hardness and corrosion and wear resistance, but the high velocities at which they are applied result in an inherently porous structure that requires some type of remediation. This study evaluates the effectiveness of ultrasonic aluminum phosphate sealing treatments on plasma sprayed Al 2 O 3 -40TiO 2 ceramic coatings. The sealants were applied with and without ultrasonication (20-40 kHz) and were assessed using SEM/EDX analysis, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). Test data indicate that optimum sealing, corresponding to the highest values of corrosion protection and erosion resistance, are achieved under ultrasonication at 30 kHz for 5 hours.
Proceedings Papers
ITSC 2021, Thermal Spray 2021: Proceedings from the International Thermal Spray Conference, 758-764, May 24–28, 2021,
Abstract
PDF
Abstract This study investigates the microstructure and hardness of coatings produced by atmospheric plasma spraying using a commercial (Al,Cr) 2 O 3 solid solution (ss) powder blended with various amounts of TiO 2 . The microstructures were analyzed using SEM, EDS, and XRD measurements. It was shown that blending with TiO 2 reduces porosity and defect density while increasing deposition efficiency and microhardness. Small amounts of Ti in ss (Al,Cr) 2 O 3 splats were detected in coatings prepared from blends with higher TiO 2 content. Variations in aluminum and chromium content were also observed.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 107-111, March 4–6, 2002,
Abstract
PDF
Abstract The field of application of ceramic and ceramic composite layers has expanded from sensitive biomedical applications to the area of aggressive industrial environments. Plasma spraying as one of the thermal spraying processes is very popular among the various coating processes. However, layers that are produced with this method are not free of defects and require post-treatment in order to obtain the desired layer properties. In this paper, both the original layers and the layers processed with the microwave polishing process are monitored in two different test environments. Investigations of the physical (porosity), mechanical (hardness and adhesive tensile strength), and functional (wear resistance) properties are carried out. It turned out that these evaluation techniques can be used to evaluate the quality of the layers. The experimental procedure for the tests is briefly presented. The results are discussed using illustrations. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 127-129, March 4–6, 2002,
Abstract
PDF
Abstract The research work described in this paper is a collaborative study between the two universities (U.L.B. and U.T.B.M.) in the field of plasma sprayed ceramic coatings. The aim is to prepare nanostructured coatings with enhanced properties based on micrometric size titanium dioxide doped with synthesized silicon dioxide nanometric size particles. Nanoscalline powders made of silicon dioxide are first produced from the gas phase in high-frequency induction plasma reactors. The powders are then spray-dried in order to produce a homogeneous mixture of micro- and nano-crystalline oxide powders, which are suitable for DC plasma spraying. The layers are analyzed and characterized. The nanocrystalline particles are distributed homogeneously in the layer composite. An HF induction plasma system is used as the spray system. Results of aluminum oxide from conventional powders are discussed. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 130-135, March 4–6, 2002,
Abstract
PDF
Abstract Various processes are used to manufacture the nanostructured materials, such as the sol-gel process, the DC-MSIP process, and the HF-MSIP process. It is also possible that the nanostructures can also be produced in a short time using a thermally activated coating process. Zirconium oxide and aluminum oxide are the most important oxide ceramics. Both have a wide range of applications. In this paper, nanostructured layers of zirconium and aluminum oxide are produced with atmospheric plasma spraying. The layers are characterized with a scanning electron microscope, a transmission electron microscope, and an X-ray phase analyzer. Dense nano-structured oxide layers (zirconium oxides and aluminum oxides) with high microhardness are produced using the atmospheric plasma spray process. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 196-201, March 4–6, 2002,
Abstract
PDF
Abstract The operating temperature of the combustion chamber of heavy-duty gas turbines has been continually increased in order to improve engine power and efficiency. Part of this improvement is due to the use of ceramic thermal barrier coatings (TBCs), which reduce thermal flow from the combustion gas to the metallic structural part of the components. The most traditional deposition technique for bond coats on combustion chamber components is Air Plasma Spray; whereas this technology is the optimum one for ceramic coatings, due to air entrapment in the plasma jet significant oxidation of Al is produced during bond coats deposition. The thermal design of a thick porous TBC able to reduce the heat flow to the minimum allowable by the materials temperature limits is performed. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 202-207, March 4–6, 2002,
Abstract
PDF
Abstract In the graded structure, the material, which has a higher coefficient of thermal expansion and good strength (YSZ), is applied in areas where high thermal stresses occur and where crack growth reaches critical values. A material with outstanding high temperature stability was used on the outer surface, where the temperatures during use can exceed the maximum temperatures for long-term use of YSZ. This article describes the manufacturing process of these structures by plasma spraying with a double injector system. The microstructure of these layers is described in detail. Thermal cycling tests with surface temperatures above 1200 deg C are carried out on these graded and stepped WDS systems. The results indicate a considerable increase in service life compared to the non-graded structures, which leads to the conclusion that this concept is well suited for the application. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 213-219, March 4–6, 2002,
Abstract
PDF
Abstract This paper discusses the application of electrical insulation on glass ceramic. Morphology of splats, phase transformation, mechanical and electric properties of plasma-sprayed ceramic coatings on glass ceramic are studied. It is observed that the preheating of substrate during deposition of glass ceramic is necessary, since bounding mechanism between coating and glass substrate is mainly of chemical nature. However, high preheating temperature causes also large residual stress in the coating. In order to reduce those, substrate cooling must be activated starting the second deposition step. Further spray parameters such as plasma power and powder feed rate must be also reduced in order to reduce the residual stress in the coating. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 220-224, March 4–6, 2002,
Abstract
PDF
Abstract A composite system that combines different properties of two materials in one composite is the coating of flexible fiber fabrics, with hard and wear-resistant structural materials on the one hand and with functional ceramic surfaces on the other hand. Both layer systems are produced using thermal spraying. In this paper, aramid and mullite light fiber fabrics are coated by atmospheric plasma spraying. To check the suitability of the process for as many technical applications as possible, different ceramic materials are used. Through the additional use of metallic adhesion promoter layers such as AlSi, multi-layer systems with high adhesive tensile strength are implemented. The results show that the use of bio-inert and biocatalytic layer materials, such as titanium dioxide and aluminum oxide, and bioactive materials, such as hydroxyapatite, enables this concept to be used in various areas of biomedical technology. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 330-334, March 4–6, 2002,
Abstract
PDF
Abstract The aluminum oxide ceramic coatings are widely used as wear and friction-resistant and insulation coatings. The atmosphere plasma spraying (APS) is a most used method for preparing alumina coating. Alumina coatings were made using low power plasma spraying. The powder was injected directly into the area between the cathode and anode in the plasma torch and the conveying gases were introduced into the plasma jet. The results show that the hardness of the aluminum oxide coatings applied using low-power plasma spraying and an internal injection system is higher than the coatings produced using APS with external injection. The plasma spray energy can be reduced by the internal feed powder system. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 488-493, March 4–6, 2002,
Abstract
PDF
Abstract The atmospheric plasma spraying process and the high velocity oxy-fuel (HVOF) spraying process are used to produce ceramic layers from titanium suboxide powder. Titanium suboxide powder is made from commercially fused and ground powders by reduction with hydrogen. Two powder particle sizes, which were produced for both atmospheric plasma spraying and for the HVOF spraying process, were used in tests. Originally melted and crushed powder fractions served as a reference powder. Furthermore, hardness, wear resistance, and electrical resistance were determined. All titanium oxide layers showed high wear resistance, with HVOF-sprayed layers exhibiting higher wear resistance than the layers produced with the atmospheric plasma spraying process. Atmospheric plasma-sprayed layers, on the other hand, are characterized by higher electrical conductivity. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 573-579, March 4–6, 2002,
Abstract
PDF
Abstract IR thermography offers efficient methods for optimizing thermally sprayed layer composites. The quality of these layer composites depends crucially on the temperature control during the coating process. With the help of thermography, the effect on the temperature distribution when changing any of these process parameters can be precisely observed. In this paper, these methods for the optimization of plasma sprayed planar layer composites of light metal substrates and ceramics, steel substrates, and ceramics, as well as glass substrates and ceramics are applied and discussed. First, the temperature distribution on the component is recorded over the entire coating process. In a further step, a correlation is established between temperature control during the coating process and the resulting internal stress distribution in the layer composite. It is observed that the burner kinematics alone has a significant influence on the resulting residual stress distributions of the layer composite. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 606-609, March 4–6, 2002,
Abstract
PDF
Abstract To investigate the accuracy of the sin square Psi method, in this paper, a four-point bending test is developed with which it is possible to load layers with defined tensile stresses. Then, the "effective surface E-modulus," which is calculated from the XRD measurements and the deflection, and the "volume E-modulus," which is calculated from the deflection and the applied load, are presented. High-density stainless steel is applied using HVOF, while the ceramic layers are produced using water-stabilized plasma spraying. The steel layers show a volume of elasticity that is twice as high as that of the surface elasticity module. No surface tension was observed in the ceramic layers during bending. This can be explained by the opening of crack structures as a result of tensile stress. In contrast to this, the pores can be expected to close under pressure loads and thus an increase in the stresses. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 639-643, March 4–6, 2002,
Abstract
PDF
Abstract This article reports on a method for densifying thermally sprayed layers by arc plasma sintering (SPS). Thermal spray ceramic coatings consist from relative high percentage of porosity compared than that of metallic coatings. An investigation of the metallurgical and mechanical properties of flame-sprayed zirconia coatings after SPS at various temperatures and loadings condition was performed. The results obtained in the present work can be summarized as follows: bond strength and microhardness of coating after SPS is increased by three times compared than as-sprayed coating, and X-ray diffraction analysis indicates that the phase of zirconium dioxide-25MgO coating was influenced the physical properties of coating. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 900-904, March 4–6, 2002,
Abstract
PDF
Abstract Thermally grown oxides (TGO) form at interfaces between the upper thermal insulation layers (TBCs) and the bond coats during operation. Macro cracks can be observed in many places in the TGO. The formation of macrocracks would reduce adhesion or lead to areas of stress peaks. To improve the adhesion, a modified powder for the boncoat was developed by adding cerium and silicon to the conventional MCrAlY. This paper investigates two kinds of TBC, which are a conventional CoNiCrAlY and a developed CoNiCrAlYCeSi bond coats. These TBCs are compared with regard to the oxidation behavior and the bond strength of the interface. To measure the adhesive strength, four-point bending tests are carried out with the normal TBC and the TBC with a modified bond coat. It is observed that the modified variant has a higher adhesive strength. The reason for this could be a reduction in the formation of mixed oxides. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 960-964, March 4–6, 2002,
Abstract
PDF
Abstract Semiconductor manufacturing apparatuses have begun to employ dry processes instead of conventional wet processes, based on the associated benefits in terms of automation, productivity, and environmental protection. This paper investigates the methods for forming an oxide-based dielectric ceramic layer on the aluminum base, a layer that has high adsorptive and stable electric properties. It discusses the electrostatic chuck, and describes the relationship between the characteristics of the aluminum oxide-titanium dioxide coating formed by the low-pressure plasma-spraying method and the resulting performance of the electrostatic chuck. The advantages of deoxidation and the change in the specific resistance of titanium dioxide during the spraying process were used to produce the layer. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 1020-1023, March 4–6, 2002,
Abstract
PDF
Abstract This paper presents the results of laser treatment of aluminum oxide + 3wt.% titanium dioxide ceramic coatings deposited by detonation spraying. The solidification process during the laser melting of detonation-sprayed layers made of ceramic powder with a layer thickness of 100 micrometer is investigated. A stainless steel is selected as the substrate, on which a nickel adhesive layer, which oxidized at 923 K in air for one hour, is applied. A carbon dioxide laser is used for melting. Both the sprayed and remelted layers are examined by means of scanning electron microscopy and X-ray diffractometry. The microstructure changes significantly due to the laser remelting. The originally laminar structure is transformed into a fine, pore-free columnar structure in which the grains are oriented perpendicular to the interface between the layer and the substrate. The melted-in zones contain alpha-aluminum oxide as the main phase and are characterized by high micro-hardness. Paper includes a German-language abstract.
Proceedings Papers
ITSC 2002, Thermal Spray 2002: Proceedings from the International Thermal Spray Conference, 1038-1041, March 4–6, 2002,
Abstract
PDF
Abstract Within the atmospheric plasma spray process the main spray parameters which determine coating properties are the thermal and kinetic energy of the spray particles at impact on the surface of the substrate. Especially the thermal energy of the particles is influenced by plasma flame properties and the interaction between the plasma and particles. In general Ar-H2- and Ar-He-mixtures are used in the atmospheric plasma spraying process. Varying the composition of the plasma gas by adding He, respectively H2 leads to different behaviour of the plasma flame especially in terms of viscosity, thermal conductivity and enthalpy. Using ternary mixtures it is possible to obtain improved coating properties for certain oxide spray materials. Al2O3-TiO2- and ZrO2-8Y2O3-coatings were examined using Ar-H2-mixtures in comparison to SPRAL 22 (Ar, H2, He) gas from Air Liquide. For the materials improved coating properties regarding bond strength and porosity were verified and an increased deposition efficiency was determined at the same time.
Proceedings Papers
ITSC2000, Thermal Spray 2000: Proceedings from the International Thermal Spray Conference, 423-428, May 8–11, 2000,
Abstract
PDF
Abstract Cold work and heat treatment influence the mechanical properties, residual stress-state, and corrosion resistance of austenitic stainless steels. In this study we have examined changes in the defect substructure and microstructure of Type 304 stainless steel resulting from surface preparation, and deposition of bond coats and thick ceramic coatings using plasma spray methods. The structure of the stainless steel was examined as a function of depth from the coating surface using optical and transmission electron microscopy, and x-ray diffraction. Grit blasting was found to severely cold work the material to a depth of tens of microns, and the amount of cold work varied with measured abrasive particle velocity. The heat input to the surface as a result of depositing a metallic bond coat or thick ceramic coating resulted in substantial annealing of the cold work imparted into the substrate by surface preparation. There was, however, no evidence of change in grain size near the substrate-coating interface that could be attributed to recrystallization or grain growth in the substrate.