Damage mechanisms and lifetime behavior of plasma-sprayed thermal barrier coating systems for gas turbines — Part II: Modeling

2008 ◽  
Vol 202 (24) ◽  
pp. 5901-5908 ◽  
Author(s):  
Tilmann Beck ◽  
Roland Herzog ◽  
Olena Trunova ◽  
Marita Offermann ◽  
Rolf W. Steinbrech ◽  
...  
Keyword(s):  
Thermal Barrier Coating ◽  
Gas Turbines ◽  
Thermal Barrier ◽  
Damage Mechanisms ◽  
Barrier Coating ◽  
Plasma Sprayed

scholarly journals A Combustor Can With 1.8 mm Thick Plasma Sprayed Thermal Barrier Coating

1998 ◽  
Author(s):  
Jan Wigren ◽  
Jens Dahlin ◽  
Mats-Olov Hansson
Keyword(s):  
Thermal Barrier Coating ◽  
Film Cooling ◽  
Gas Turbines ◽  
Thermal Barrier ◽  
Current State ◽  
Barrier Coating ◽  
Component Test ◽  
Before And After ◽  
Plasma Sprayed ◽  
Cooling Air

The benefits of thermal barrier coatings for protection of combustor walls are well known. However, the trend to higher combustor inlet temperatures and the reduced availability of cooling air leads to a demand for better insulation performance from the thermal barrier coating (TBC). This is of particular benefit for low emission combustors where wall quenching effects need to be minimised and often hot side cooling is not permissible. A combustor can, for advanced stationary gas turbines, with 1.8 mm thick thermal barrier was designed and tested. The can was compared to a combustor can with a thermal barrier coating sprayed with current state-of-the-art methods, but to the same thickness. Steps to optimise performance were taken in all development stages. The design allowed easy spray geometries, improved edges and no film cooling. Spraying was optimised in order to achieve a segmented microstructure for reduction of stresses (by decrease of the Young’s Modulus in the coating) and increase compliance of the coating. Testing in component test rigs showed excellent results. The lifetime of the optimised combustor can was beyond test capabilities, whereas the reference combustor failed immediately. Metallographic and X-ray characterisation before and after component rig testing was performed and revealed features that explain the superiority of the segmented thermal barrier coating. This work has been funded by the CEC under the contract BRE-CT94-0936.

HOT CORROSION OF CERIA-YTTRIA STABILIZED ZIRCONIA PLASMA SPRAYED THERMAL BARRIER COATING BY EUTECTIC VANDIUM PENTAOXIDE-SODIUM SULFATE

2018 ◽  
Vol 18 (1) ◽  
pp. 182-192 ◽  
Author(s):  
Mohammed J Kadhim ◽  
Mohammed H Hafiz ◽  
Maryam A Ali Bash
Keyword(s):  
Thermal Barrier Coating ◽  
Hot Corrosion ◽  
Monoclinic Phase ◽  
Volume Fraction ◽  
High Volume ◽  
Thermal Barrier ◽  
Air Plasma ◽  
Plan View ◽  
Barrier Coating ◽  
Plasma Sprayed

The high temperature corrosion behavior of thermal barrier coating (TBC) systemconsisting of IN-738 LC superalloy substrate, air plasma sprayed Ni24.5Cr6Al0.4Y (wt%)bond coat and air plasma sprayed ZrO2-20 wt% ceria-3.6 wt% yttria (CYSZ) ceramic coatwere characterized. The upper surfaces of CYSZ covered with 30 mg/cm2 , mixed 45 wt%Na2SO4-55 wt% V2O5 salt were exposed at different temperatures from 800 to 1000 oC andinteraction times from 1 up to 8 h. The upper surface plan view of the coatings wereidentified for topography, roughness, chemical composition, phases and reaction productsusing scanning electron microscopy, energy dispersive spectroscopy, talysurf, and X-raydiffraction. XRD analyses of the plasma sprayed coatings after hot corrosion confirmed thephase transformation of nontransformable tetragonal (t') into monoclinic phase, presence ofYVO4 and CeVO4 products. Analysis of the hot corrosion CYSZ coating confirmed theformation of high volume fraction of YVO4, with low volume fractions of CeOV4 and CeO2.The formation of these compounds were combined with formation of monoclinic phase (m)from transformation of nontransformable tetragonal phase (t').

scholarly journals Progress in Novel Electrodeposited Bond Coats for Thermal Barrier Coating Systems

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4214
Author(s):  
Kranthi Kumar Maniam ◽  
Shiladitya Paul
Keyword(s):  
Gas Turbine ◽  
Thermal Barrier Coating ◽  
Gas Turbines ◽  
High Performance ◽  
Turbine Engines ◽  
Thermal Barrier ◽  
Gas Turbine Engines ◽  
Potential Cost ◽  
Bond Coats ◽  
Barrier Coating

The increased demand for high performance gas turbine engines has resulted in a continuous search for new base materials and coatings. With the significant developments in nickel-based superalloys, the quest for developments related to thermal barrier coating (TBC) systems is increasing rapidly and is considered a key area of research. Of key importance are the processing routes that can provide the required coating properties when applied on engine components with complex shapes, such as turbine vanes, blades, etc. Despite significant research and development in the coating systems, the scope of electrodeposition as a potential alternative to the conventional methods of producing bond coats has only been realised to a limited extent. Additionally, their effectiveness in prolonging the alloys’ lifetime is not well understood. This review summarises the work on electrodeposition as a coating development method for application in high temperature alloys for gas turbine engines and discusses the progress in the coatings that combine electrodeposition and other processes to achieve desired bond coats. The overall aim of this review is to emphasise the role of electrodeposition as a potential cost-effective alternative to produce bond coats. Besides, the developments in the electrodeposition of aluminium from ionic liquids for potential applications in gas turbines and the nuclear sector, as well as cost considerations and future challenges, are reviewed with the crucial raw materials’ current and future savings scenarios in mind.

Sign in / Sign up

Export Citation Format

Share Document