テラヘルツ波イメージングによる遮熱コーティングの非破壊検査における空間分解能評価

抄録

The spatial resolution of THz imaging in nondestructive testing of thermal barrier coating was evaluated. The instrumental resolution was evaluated using a test pattern and was found to be about 0.6mm. The test pattern under a YSZ sample of thickness 1.25mm could be identified from the spatial distribution of the wave reflected from the back side of the YSZ sample, with a planar spatial resolution of about 1mm. THz imaging successfully detected an artificial defect of 1mm×1mm under the topcoat in a TBC sample. The results showed the possibility of detection of surface defects under the topcoat by THz imaging.