The specimens were subjected to UT volumetric scanning using the custom made software code Robotest© for FV-Scan UT NDE
Pulse-echo immersion volumetric UT scans were carried out using a focused (49.6 mm focal length), high frequency (15 MHz) transducer for maximum resolution
The oscillator/detector was set up at 90 dB gain and medium damping
The digital oscilloscope was set up at 1 V/div, 0.5 micros/div, and sampling frequency 100 MHz, resulting in 500 samplings detected for each UT waveform
Each specimen was scanned over an area of 110 x 155 mm with scan step 1 mm. After UT NDE the delaminated area was measured