- AutorIn
- Martin Dressler
- Titel
- Sol-gel preparation and characterization of corundum based ceramic oxidation protection coatings
- Zitierfähige Url:
- https://nbn-resolving.org/urn:nbn:de:bsz:105-8553447
- Datum der Einreichung
- 27.09.2006
- Datum der Verteidigung
- 08.12.2006
- Abstract (EN)
- The Ni-base superalloy, IN-718, has been coated with alumina sols. Coated surfaces, carrying alumina layers having thicknesses between 0.6 μm and 3.6 μm show a significantly reduced oxidation rate when compared with uncoated reference surfaces, even if heating temperature is increased up to 900 °C and heating time is extended to 800 h. Alumina layers were prepared via sol-gel processing using a modified Yoldas procedure to obtain alumina sols. No change in rheological sol behavior was observed for more than 1 year of aging under static conditions at room temperature. Depending on pH value, modified Yoldas sols contain a manifold of Al species, among them Al13 polycations. Thermal evolution of sol derived alumina powders depends on Al speciation of parent sols. Depending on sol composition, both gamma-Al2O3 and eta-Al2O3 occur as intermediate transition aluminas. Phase composition and gas phase velocity influence oxygen permeability of thin layers prepared with modified Yoldas sols.
- Freie Schlagwörter (DE)
- Oxidationsschutz, Sol-Gel, Alumosole, Inconel 718, Permeation, Phasentransformation, eta-Al2O3, DTA, XRD, NMR, Rheologie, Aluminiumoxidkeramik, Schutzschicht, Oxidation, Sol-Gel-Verfahren
- Klassifikation (DDC)
- 620
- Klassifikation (RVK)
- ZM 7620
- GutachterIn
- Dr. sc. nat. Marianne Nofz
- Prof. Dr.-Ing. habil. Christos G. Aneziris
- Prof. Dr.-Ing. habil. Horst Biermann
- BetreuerIn
- Dr. sc. nat. Marianne Nofz
- Den akademischen Grad verleihende / prüfende Institution
- TU Bergakademie Freiberg, Freiberg
- URN Qucosa
- urn:nbn:de:bsz:105-8553447
- Veröffentlichungsdatum Qucosa
- 23.07.2009
- Dokumenttyp
- Dissertation
- Sprache des Dokumentes
- Englisch