Gadolinium zirconate/YSZ thermal barrier coatings: Mixed-mode interfacial fracture toughness and sintering behavior
| Autor: | Matthias Oechsner, Emine Bakan, Martin Frommherz, Robert Vaßen, Alfred Scholz |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
010302 applied physics
Toughness Materials science Sintering 02 engineering and technology Surfaces and Interfaces General Chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics Microstructure 01 natural sciences Zirconate Surfaces Coatings and Films Thermal barrier coating 0103 physical sciences Monolayer Materials Chemistry Cubic zirconia Composite material 0210 nano-technology Yttria-stabilized zirconia |
| Zdroj: | Surface and Coatings Technology. 286:119-128 |
| ISSN: | 0257-8972 |
| DOI: | 10.1016/j.surfcoat.2015.12.012 |
| Popis: | In this work, the delamination toughness and the sintering behavior of modern double-layer thermal barrier coatings of type gadolinium zirconate (GZO)/yttrium-stabilized zirconia (YSZ) are investigated in detail. These properties mainly determine the strain tolerance and thus the performance of thermal barrier coatings (TBCs). The delamination toughness was determined using a modified four-point bending setup. It is shown that the delamination behavior differs significantly from conventional monolayer coatings and is highly dependent on the specific microstructure of the GZO layer. The stiffness and sintering behavior of freestanding GZO layers were determined using impulse excitation, a test method sensitive to the global stiffness of the ceramic coating. The increase in stiffness is thereby correlated to microstructural changes, explicitly the healing of micro-cracks and the sintering of inter-lamellar cracks and unmolten particles. The results reveal that the specific spray structure of GZO has a great influence on the sinter stability which results in a characteristic temperature dependency. In this case the GZO coatings have an advantage in comparison to conventional YSZ coatings at temperatures above 1300 °C. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect