000019785 001__ 19785
000019785 005__ 20240711092255.0
000019785 0247_ $$2ISSN$$a1866-1793
000019785 0247_ $$2Handle$$a2128/4566
000019785 020__ $$a978-3-89336-783-2
000019785 037__ $$aPreJuSER-19785
000019785 041__ $$aEnglish
000019785 082__ $$a500
000019785 082__ $$a333.7
000019785 082__ $$a620
000019785 1001_ $$0P:(DE-Juel1)VDB88818$$aSong, Peng$$b0$$eCorresponding author$$uFZJ
000019785 245__ $$aInfluence of Material and Testing Parameters on the Lifetime of TBC Systems with MCrAlY and NiPtAl Bondcoats
000019785 260__ $$aJülich$$bForschungszentrum Jülich GmbH Zentralbibliothek, Verlag$$c2011
000019785 300__ $$aV, 126 S.
000019785 3367_ $$0PUB:(DE-HGF)11$$2PUB:(DE-HGF)$$aDissertation / PhD Thesis
000019785 3367_ $$0PUB:(DE-HGF)3$$2PUB:(DE-HGF)$$aBook
000019785 3367_ $$02$$2EndNote$$aThesis
000019785 3367_ $$2DRIVER$$adoctoralThesis
000019785 3367_ $$2BibTeX$$aPHDTHESIS
000019785 3367_ $$2DataCite$$aOutput Types/Dissertation
000019785 3367_ $$2ORCID$$aDISSERTATION
000019785 4900_ $$0PERI:(DE-600)2445288-9$$aSchriften des Forschungszentrums Jülich : Energie & Umwelt / Energy & Environment$$v137
000019785 502__ $$aRWTH Aachen, Diss., 2011$$bDr. (Univ.)$$cRWTH Aachen$$d2011
000019785 500__ $$3POF3_Assignment on 2016-02-29
000019785 500__ $$aRecord converted from JUWEL: 18.07.2013
000019785 500__ $$aRecord converted from VDB: 12.11.2012
000019785 520__ $$aThe oxidation behavior of the bond coat is an important factor determining the lifetime of thermal barrier coatings (TBC) in the advanced gas turbine components. In the present work, the effect of various testing parameters, such as hot/cold dwell time, heating/cooling rate, atmosphere composition on the bondcoat oxidation and associated TBC lifetime has been investigated. The range of coating systems included Electron Beam - Physical Vapor Deposited (EB-PVD) and Air Plasma Sprayed (APS) TBC´s with MCrAlY (M = Ni, Co) and NiPtAl- bondcoats of various compositions. The effect of the testing parameters strongly depended on the type and properties of the studied system. The lifetime of EB-PVD TBC systems with conventional MCrAlY and NiPtAl bondcoats forming uniform, flat alumina scales was found to be limited by critical scale thickness, upon which a rapid crack propagation at the scale/bondcoat interface results in macroscopic failure. The lifetime of such systems was found to be affected by factors, which influence the scale growth rate and adherence (in particular by oxygen partial pressure (pO$_{2}$) and water vapor content in the test gas in the case of MCrAlY), whereas the temperature cyclic frequency showed no significant effect. NiPtAl bondcoats showed a superior behavior than the conventional MCrAlY-bondcoats due to slower scale growth rate and better scale adherence. For EB-PVD TBC systems with Zr-doped MCrAlYbondcoats the lifetime is mainly determined by the crack growth rate in the inhomogeneous inwardly growing oxide scales, whereas the lifetime is not dependent on the pO$_{2}$ but rather on the cyclic frequency. For APS TBC systems the bondcoat oxidation is only one of several factors determining the ceramic topcoat lifetime. Therefore the oxide scale adherence is of less importance for lifetime of APS TBCs as compared to EBPVD TBCs. For the former systems, the cracks initiated at the convex asperities of the rough oxide scale / bondcoat interface need to propagate through the TBC to cause macroscopic failure. The rate of crack propagation in the TBC is a critical step, which depends substantially on its microstructural properties. In addition to the TBC-porosity the bondcoat roughness profile is shown to be an important parameter, which to a large extent determines the rate of crack initiation and propagation. Higher Co-content in the bondcoat was found to stabilize its microstructure thereby lowering the CTE-mismatch stress in the ceramic topcoat thus extending the TBC-lifetime. The major drawback of high Co-contents was that such bondcoats are prone to form fast-growing spinel oxides. This effect, which was especially pronounced on rough surfaces could be suppressed by only a minor (few microns) enrichment of Al on the bondcoat surface prior to TBC-deposition produced by heat-treatment in high vacuum. With respect to the effects of experimental parameters it was found that contrary to EB-PVD TBC systems a higher cycle frequency leads to shortening of the APS TBC lifetime, whereas higher water vapor content had no significant influence. The results of the present work indicate that the lifetime of the TBC systems with MCrAlY bondcoats would be shorter than that required for long-term operation (25 000 hours) at the envisaged operating temperature of 1000°C. Under such circumstances using NiPtAl-type of bondcoats or perhaps Pt-modified MCrAlY-bondcoats would be an option to obtain the necessary lifetime extension, which can even justify the high cost of metallic Pt.
000019785 536__ $$0G:(DE-Juel1)FUEK402$$2G:(DE-HGF)$$aRationelle Energieumwandlung$$cP12$$x0
000019785 655_7 $$aHochschulschrift$$xDissertation (Univ.)
000019785 8564_ $$uhttps://juser.fz-juelich.de/record/19785/files/Energie%26Umwelt_137.pdf$$yOpenAccess
000019785 8564_ $$uhttps://juser.fz-juelich.de/record/19785/files/Energie%26Umwelt_137.jpg?subformat=icon-1440$$xicon-1440$$yOpenAccess
000019785 8564_ $$uhttps://juser.fz-juelich.de/record/19785/files/Energie%26Umwelt_137.jpg?subformat=icon-180$$xicon-180$$yOpenAccess
000019785 8564_ $$uhttps://juser.fz-juelich.de/record/19785/files/Energie%26Umwelt_137.jpg?subformat=icon-640$$xicon-640$$yOpenAccess
000019785 909CO $$ooai:juser.fz-juelich.de:19785$$pdnbdelivery$$pVDB$$pdriver$$popen_access$$popenaire
000019785 915__ $$0StatID:(DE-HGF)0510$$2StatID$$aOpenAccess
000019785 9141_ $$y2011
000019785 9131_ $$0G:(DE-Juel1)FUEK402$$bEnergie$$kP12$$lRationelle Energieumwandlung$$vRationelle Energieumwandlung$$x0
000019785 9132_ $$0G:(DE-HGF)POF3-119H$$1G:(DE-HGF)POF3-110$$2G:(DE-HGF)POF3-100$$aDE-HGF$$bForschungsbereich Energie$$lEnergieeffizienz, Materialien und Ressourcen$$vAddenda$$x0
000019785 920__ $$lyes
000019785 9201_ $$0I:(DE-Juel1)IEK-2-20101013$$gIEK$$kIEK-2$$lWerkstoffstruktur und -eigenschaften$$x0
000019785 970__ $$aVDB:(DE-Juel1)134772
000019785 9801_ $$aFullTexts
000019785 980__ $$aVDB
000019785 980__ $$aConvertedRecord
000019785 980__ $$aphd
000019785 980__ $$aI:(DE-Juel1)IEK-2-20101013
000019785 980__ $$aUNRESTRICTED
000019785 980__ $$aJUWEL
000019785 980__ $$aFullTexts
000019785 981__ $$aI:(DE-Juel1)IMD-1-20101013