Suspension plasma spraying (SPS) has become an interesting method for the production of thermal barrier coatings for gas turbine components. The development of the SPS process has led to structures with segmented vertical cracks or column-like structures that can imitate strain-tolerant air plasma spraying (APS) or electron beam physical vapor deposition (EB-PVD) coatings. Additionally, SPS coa...

Following the successful application of Electron Beam (EB) Physical Vapour Deposition (PVD) Thermal Barrier Coatings (TBCs) to moving parts of turbine engines the erosion resistance of these coatings has been of interest among researchers. However, although there are a number of papers on the erosion rate of these coatings, little has been reported on their erosion mechanism. This paper provide...

Thermal barrier coatings (TBCs) deposited by Electron-beam physical deposition (EBPVD) protect the turbine blades situated at the high pressure sector of the aircraft and stationary turbines. It is an important task to uphold low thermal conductivity in TBCs during long-term service at elevated temperatures. One of the most promising methods to hlfil this task is to optimize the properties of P...

Thermal barrier coatings (TBCs), consisting of physical vapor deposited (PVD) partially stabilized zir-conia (PSZ, 8 wt. %Y203) and a diffusion aluminide bond coat, were characterized as a function of time after oxidative isothermal heat treatment at 1373 K in air. The experimental characterizations was conducted by X-ray diffraction analysis and scanning electron microscopy (SEM) with energy-d...

The thermal barrier coatings (TBCs) by gas tunnel-type plasma spraying exhibited ceramic-composite features consisting of a host oxide matrix ceramic with an embedded second phase material. The densities of the composite TBC were found to be higher than those sprayed with 100wt% ZrO2 or Al2O3. In the coatings produced with powder mixtures of 50wt%, the embedded splats are found to have a relati...

Thin layers of thermal barrier coating (TBCs) are applied to metallic components of heat engines to reduce metal temperatures and to provide environmental protection. This results in increased engine efficiency and prolonged operational life. Of special current interest is the use of TBCs in aircraft engines. The TBCs, often yttria-stabilized zirconia (YSZ), are deposited on nickel or cobalt-ba...

NiCr₂O₄ as a potential protection for thermal barrier coatings (TBCs) against the attack of molten calcium-magnesium-alumino-silicate (CMAS) was studied by a CMAS-contacting experiment. Atmospheric plasma sprayed coatings and sintered bulk materials were fabricated, covered with CMAS deposits, and exposed to 1200 °C for 24 h. Nano-sized CMAS-NiCr₂O₄ mixed powder was manufactured by ball milling...

ÐThe durability of residually compressed coatings, particularly thermal barrier coatings (TBCs), is governed by events occurring at the interface with the substrate. In general, failure involves the sequential nucleation growth and coalescence of separations in the presence of imperfections and defects. The growth and coalescence phases are analyzed. Remnant ligaments are expected from the mech...

The microwave drill is a novel process for creating shaped holes in nonconductive materials. Its inherent material selectivity makes the microwave drill ideally suited for the controlled removal of ceramic coatings from underlying metallic substrates. In this paper, it is shown that the microwave drill process can drill through ceramic thermal barrier coatings (TBCs) to uncover an array of simu...

Thermal barrier coatings (TBCs) are a fundamental technology used in high-temperature applications to protect superalloy substrate components. However, extreme environments present many challenges for TBCs, such as the degradation of their thermal and mechanical properties. Hence, highly insulating, long-life TBCs must be developed meet higher industrial efficiency. This paper reviews main fact...