NONDESTRUCTIVE CHARACTERIZATION OF CERAMIC COMPOSITES USED AS COMBUSTOR LINERS IN ADVANCED GAS-TURBINES

Nondestructive characterization (NDC) methods, which can provide full- field information about components prior to and during use, are critic al to the reliable application of continuous fiber ceramic matrix comp osites in high-firing-temperature (> 1350 degrees C) gas turbines. [Fo r combustor liners, although they are nonmechanical load-bearing compo nents, both thermal characteristics and mechanical integrity are vital ly important.] NDC methods being developed to provide necessary inform ation include x-ray computed tomography (mainly for through-wall densi ty and delamination detection), infrared-based thermal diffusivity ima ging, and single-wall through-transmission x-ray imaging (mainly for f iber content and alignment detection). Correlation of the data obtaine d from NDC methods with subscale combustor liner tests have shown posi tive results at thermal cycling temperatures from 700 degrees C to 117 7 degrees C.