Recent Developments in the Characterization of Anisotropic Void Populations in Thermal Barrier Coatings Using Ultra-Small Angle X-ray Scattering

Published

January 1, 2003

Author(s)

Gabrielle G. Long, T A. Dobbins, Andrew J. Allen, J Ilavsky, P Jemain, A Kulkarni, H Herman

Abstract

Thermal barrier coatings (TBC) have complex void microstructures which control their in service properties. In the research reported here, ultra-small-angle X-ray scattering (USAXS) has been used to characterize anisotropic void populations in TBC s. A new analysis method has been developed for characterizing the voids in three dimensions. The anisotropy in the microstructure at a given length scale associated with a value of the scattering vector, [Q] gives rise to changes in scattered intensity as a function of the sample orientation. By measuring the scattered intensity at fixed [Q] as the sample is rotated about the beam, the distribution of the scattering population(s) having at this length scale is determined. Using an anisotropic modeling method, the void orientation distribution, void size distribution, shape, and volume fraction information is determined for up to four different void populations. This paper illustrates the use of three-dimensional anisotropic USAXS modeling for the analysis of scattering from voids in TBC microstructures deposited by electron beam physical vapor deposition.

Proceedings Title

Composites, Advanced Ceramics, Materials, and Structures, Annual Conference | 27th | | American Ceramic Society

Volume

24

Issue

Pt. 3

Conference Dates

January 26-31, 2003

Conference Title

Ceramic Engineering and Science Proceedings

Pub Type

Conferences

Keywords

EMPVD, microstructure, TBC, USAXS

Citation

Long, G. , Dobbins, T. , Allen, A. , Ilavsky, J. , Jemain, P. , Kulkarni, A. and Herman, H. (2003), Recent Developments in the Characterization of Anisotropic Void Populations in Thermal Barrier Coatings Using Ultra-Small Angle X-ray Scattering, Composites, Advanced Ceramics, Materials, and Structures, Annual Conference | 27th | | American Ceramic Society (Accessed April 19, 2024)