Date of download: 1/6/2018 Copyright © ASME. All rights reserved. From: Role of Platinum in Thermal Barrier Coatings Used in Gas Turbine Blade Applications J. Eng. Gas Turbines Power. 2009;132(2):022103-022103-6. doi:10.1115/1.3156814 Figure Legend: Wavelength dispersive X-ray spectra illustrating the effect of Pt on the composition of the bond coat surface in the heat-treated condition (as-polished condition): (a) spectrum derived from the surface of the simple aluminide bond coat showing the presence of refractory transition metals, (b) spectrum derived from the Pt-aluminide bond coat showing the surface to be relatively free of transition metals

Date of download: 1/6/2018 Copyright © ASME. All rights reserved. From: Role of Platinum in Thermal Barrier Coatings Used in Gas Turbine Blade Applications J. Eng. Gas Turbines Power. 2009;132(2):022103-022103-6. doi:10.1115/1.3156814 Figure Legend: Effect of the type of bond coat on the performance of thermal barrier coating systems at 1150°C with a 24-h cycling period at room temperature

Date of download: 1/6/2018 Copyright © ASME. All rights reserved. From: Role of Platinum in Thermal Barrier Coatings Used in Gas Turbine Blade Applications J. Eng. Gas Turbines Power. 2009;132(2):022103-022103-6. doi:10.1115/1.3156814 Figure Legend: Analysis of the oxide phase near the oxide bond coat interface after 96 h of exposure at 1150°C: (a) bright-field TEM image showing representative grain structure of the oxide developed by the Pt and Pt-aluminide and bond coats, (b) corresponding selected-area diffraction pattern indexed in terms of the structure of α-Al2O3, (c) energy dispersive X-ray spectrum showing the elemental composition of the oxide developed by the Pt bond coat, and (d) energy dispersive X-ray spectrum showing the elemental composition of the oxide developed by the Pt-aluminide bond coat

Date of download: 1/6/2018 Copyright © ASME. All rights reserved. From: Role of Platinum in Thermal Barrier Coatings Used in Gas Turbine Blade Applications J. Eng. Gas Turbines Power. 2009;132(2):022103-022103-6. doi:10.1115/1.3156814 Figure Legend: An example derived from the Pt-aluminide bond coat to illustrate the role of interfacial Ti-rich oxide particles in the loss of adhesion between the thermally grown oxide and bond coat (96 h of exposure at 1150°C with a 24-h cycling period at room temperature): (a) secondary electron image illustrating the morphology of the bond coat surface, voids are marked by the arrows, (b) secondary electron image illustrating the morphology of the bottom surface of top coat covered by the thermally grown oxide containing particles of Ta- and Ti-rich oxides, (c) an example illustrating the presence of Ti-rich oxide particles at the bottom of voids observed in (a), and (d) a schematic illustrating decohesion of the thermally grown oxide by formation of voids around Ti-rich oxide particles at the oxide-bond coat interface

Date of download: 1/6/2018 Copyright © ASME. All rights reserved. From: Role of Platinum in Thermal Barrier Coatings Used in Gas Turbine Blade Applications J. Eng. Gas Turbines Power. 2009;132(2):022103-022103-6. doi:10.1115/1.3156814 Figure Legend: Effect of temperature (T) on the parabolic rate constant (K) for interdiffusion between the superalloy substrate and various bond coats