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Showing 1 to 18 of 18 for “"thermal barrier coatings (TBCs)"”.
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Stress and Damage Analyses of Thermal Barrier Coatings Under Cyclic Thermal Loading Conditions
The premature failure of the thermal barrier coatings (TBCs) system is a preliminary phenomenon that can significantly limit their applications in gas turbine engines. The delamination of TBCs occurs typically at interfaces between the top coat and bond coat due to thermal mismatch stress via both …
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Hot corrosion behaviour of new candidates for thermal barrier coatings application in turbine simulated environments
Thermal barrier coatings (TBCs) are used gas turbine engines. The current material of choice (YSZ) degrades when it contacts with impurities arise from low quality fuels such vanadium and sulfur. YSZ cannot be used in temperature higher than 900˚C. Higher efficiency and performance of gas turbine …
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Cure Kinetics of Two Part Epoxy Resin and the Effect on Characterization of Thermal Barrier Coatings
… gas turbine engines by increasing power and thermal efficiencies while simultaneously reducing cost. Turbine engines operate under high temperatures and therefore thermal barrier coatings (TBCs) composed of yttria-stabilized zirconia (YSZ) play an important role in improving the performance …
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Study of microstructure effect on the thermal properties of Yttria-stabilized-Zirconia thermal barrier coatings made by atmospheric plasma spray and pressing machine
Thermal barrier coatings (TBCs) are used in gas turbine engines to achieve a higher working temperature and thus lead to better efficiency. Yttria-Stabilized-Zirconia (YSZ), a material with low thermal conductivity, is commonly used as the top coat layer to provide the thermal barrier effect. In …
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Bondcoat developments for thermal barrier coatings
… has lead to the widespread use of surface coatings technology to protect hot-section componentry from the harsh operating environment. The ongoing drive towards higher operating temperatures has lead to an interest, over the last few years, in thermal barrier coatings (TBCs). TBCs are …
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Synchrotron X-Ray Diffraction and Piezospectroscopy used for the Investigation of Individual Mechanical Effects from Environmental Contaminants and Oxide Layer Undulations in Thermal Barrier Coatings
<p>The durability of Thermal Barrier Coatings (TBCs) used on the turbine blades of aircraft and power generation engines has been known to be affected by sand particle ingression comprised of Calcium-Magnesium-Alumina-Silicate (CMAS). Previous studies have shown that these effects present …
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On the Rumpling Instability in Thermal Barrier Systems
"Thermal barrier coatings (TBCs) are protective multi-layered metal-ceramic coatings used in hot sections of jet engines and gas turbines. The TBCs are composed of a superalloy substrate, an intermediate metallic bond coat (BC) and a ceramic topcoat. The TBCs are beset by reliability problems …
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The effect of sintering and CMAS on the stability of plasma-sprayed zirconia thermal barrier coatings
State of the art thermal barrier coatings (TBCs) for gas turbine applications comprise (7 wt.%) yttria partially stabilized zirconia (7YSZ). 7YSZ offers a range of attractive functional properties – low thermal conductivity, high thermal expansion coefficient and high in-plane strain tolerance. …
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Thermal Evolution of MAS, YSZ and GZO Thermal Barrier Coating Materials in Benign and CMAS Rich Environments
Abradable thermal barrier coatings (TBCs) play a crucial role as thermal insulators and dynamic seals in turbine engines. However, the conventional choice, yttria-stabilised zirconia (YSZ), exhibits vulnerabilities, such as sintering induced stiffening, phase transformations, and susceptibility to …
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In-Situ Investigations of Calcium-Magnesium-Aluminosilicates (CMAS) Infiltration Effects on Thermal Barrier Coatings Under Extreme Environments Replicating Jet Engines
… interact and degrade the high temperature thermal barrier coatings (TBC) protecting underlying superalloy turbine blades vital to engine operation. These CMAS particulates melt within the engine and infiltrate into the ceramic coatings. In electron-beam physical vapor deposited (EB-PVD) …
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Effects Of Bond Coat Surface Preparation On Thermal Cycling Lifetime And Failure Characteristics Of Thermal Barrier Coatings
Thermal barrier coatings (TBCs) have been widely used in gas turbine engines to protect the underlying metal from high operating temperature so as to improve the durability of the components and enhance the engine efficiency. However, since the TBCs always operate in a demanding high-temperature …
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Atomistic and finite element modeling of zirconia for thermal barrier coating applications
… Due to its high melting temperature, low thermal conductivity, and high-temperature stability, zirconia based ceramics have been widely used for thermal barrier coatings (TBCs). When TBC is exposed to thermal cycling during real applications, the TBC may fail due to several mechanisms: (1) …
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Microstructural characterization of a plasma sprayed ZrO2-Y2O3-TiO2 thermal barrier coating
The use of plasma sprayed ceramic coats as thermal barrier coatings (TBCs) for the protection of metallic structures and equipment from severe thermal, abrasive and corrosive conditions has been documented extensively in the last two decades. The state-of-the-art TBCs consist of a double layer …
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Development of Advanced Internal Cooling Technologies for Gas Turbine Airfoils under Stationary and Rotating Conditions
… cost. The turbine airfoils are coated with thermal barrier coatings (TBCs) and the external surface is protected by film cooling. The internals of gas turbine blades are cooled by relatively colder air bled off from the compressor discharge. Gas turbine internals can be divided into three …
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Heat Transfer Performance Improvement Technologies for Hot Gas Path Components in Gas Turbines
… with a view towards increasing the overall thermal efficiency and specific power output. As a result of increased turbine inlet temperatures, the hot gas path components downstream of the combustor section are subjected to high heat loads. Though materials with improved temperature …
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Nondestructive Evaluation Of Thermal Barrier Coatings With Thermal Wave Imaging And Photostimulated Luminescence Spectroscopy
… beyond material limits is by applying thermal barrier coatings (TBCs) to hot section components. TBCs provide a thermal gradient between the hot gases and metallic substrate, and allow an increase in turbine inlet temperatures of 100-150ºC. However, spallation of TBCs can cause …
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Thermomechanical properties of novel lanthanum zirconate based thermal barrier coatings - an integrated experimental and modeling study
<p>Thermal barrier coatings (TBCs) are refractory materials deposited on gas turbine components, which provide thermal protection for metallic components at operating conditions. The current state-of-art TBC material is yttria-stabilized zirconia (YSZ), whose service temperature is limited to 1200 …
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Non-destructive Microstructural Evaluation Of Yttria Stabilized Zirconia, Nickel Aluminides And Thermal Barrier Coatings Using Electrochemical Impedance Spectroscopy
… should be increased in the gas turbine engines, thermal barrier coatings (TBCs) have gained significant applications in increasing the gas inlet temperatures. Insulating characteristics of ceramic TBCs allow the operation at up to 150~250 ˚C higher gas temperatures. Because of the severe turbine …