Transmission electron microscopy of isothermally oxidized EB-PVD thermal barrier coating on (Ni,Pt)Al bondcoat

    Authors

    J. W. Byeon; S. Laxman;Y. H. Sohn

    Comments

    Authors: contact us about adding a copy of your work at STARS@ucf.edu

    Keywords

    thermal barrier coating; transmission electron microscopy; isothermal; oxidation; bond coat surface preparation; grit blasting; GROWN OXIDE; OXIDATION; SCALES; Engineering, Environmental; Materials Science, Multidisciplinary

    Abstract

    The growth and microstructure of the thermally grown oxide (TGO) underneath the electron beam physical vapor deposited (EB-PVD) yttria stabilized zirconia (YSZ) topcoat were examined after short-term isothermal oxidation (1100 degrees C, up to 50 hours) for the as-coated and grit-blasted (Ni,Pt)Al bondcoats. Microstructural. analysis was carried out by a high resolution scanning transmission electron microscope equipped with bright/dark field imaging, high angle annular dark field imaging, and nano-spot energy dispersive spectroscopy. Presence of mixed oxide zone (MOZ) and a continuous Al2O3 oxide zone (COZ) was observed on the thermal barrier coating (TBC) with the as-coated (Ni,Pt)AI bondcoat. However, on the TBC with grit-blasted bondcoat, only the continuous-columnar Al2O3 scale was observed. For the as-coated type bondcoat, numerous voids were observed near the interface between MOZ and COZ after isothermal oxidation. On the other hand, COZ showed parabolic growth without any formation of voids for the grit-blasted specimens.

    Journal Title

    Eco-Materials Processing & Design Vi

    Volume

    486-487

    Publication Date

    1-1-2005

    Document Type

    Article

    Language

    English

    First Page

    149

    Last Page

    152

    WOS Identifier

    WOS:000230389400038

    ISSN

    0255-5476; 0-87849-966-0

    Share

    COinS