2830 超音波パルス反射法によるFRP板の欠陥検出性について(S37-2 非破壊評価とモニタリング(2),S37 非破壊評価とモニタリング)

抄録

This study investigated effects of the defect size, the defect location from the test surface and the fiber lamination layer patterns on thin plates of the fiber reinforced plastics (FRP), which influences the defect detection by the ultrasonic pulse echo method. The following conclusions are obtained ; Defective detection of the ultrasonic measurement influences not the fibers of glass and carbon, but the remaining bubbles in FRP of the fabric fiber lamination layer type. In thin plate becomes an ultrasonic near field zone, defective detection decreases as defect location approaches the test surface. The ultrasonic echo height F/B becomes a constant value independent of the ratio of defect area Sf/So as the hole diameter is constant. A defect ofφ0.5mm at the distance of 0.5mm from the test surface could be detected by the double crystal probe of 5MHz.