Measurements of both through-thickness and lateral thermal diffusivities are described for a SiC/SiC ceramic matrix composite material. The measurement approach is one-sided and is based on the timeresolved infrared radiometry (TRW) method in which the specimen is illuminated with a step heating pulse and the resulting temperature rise is monitored with an infrared focalpiane array. An area heating source is used for the through-thickness measurement of thermal diffusivity and a line source is used for the lateral thermal diffusivity measurement. The results indicate that the thermal diffusivity values obtained using a model assuming surface absorption and emission have to be corrected since the composites show some infrared transparency accompanied by strong scattering. Additional measurements are presented on CMC components structures with possible porosity at bonds.

Over the last decade, the ability to simulate the results of NDE has made major strides. A number of tools are now available, in various stages of development, that can accurately predict the results of rather practical measurements made on parts with complex geometries and material properties. This paper documents the results of a discussion session in which ways to best take advantage of this technical capability were considered. Included are considerations of how to most effectively couple to users, points in the life cycle of components when simulations can be most effectively used, the role of models in assessing trade-offs between various strategies for assuring reliability, and the role of models in documenting the economic benefits of NDE. Also considered are certain strategic issues concerning model development.

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