Non Destructive Testing

Applications in the field of Non-Destructive Testing

We present here some of the main applications developed and results obtained in the field of Non-Destructive-Testing using air-coupled ultrasonic techniques.

Index

I. Generation and detection of guided waves in solids using air-coupled and wideband piezoelectric transducers.

   I.a. Lamb waves in plates.

   I.b. Lamb waves in the FRP skin of sandwich structures

   I.b. Guided waves in the wall of a cylinder.

   I.c. Pseudo Lamb waves along curved surfaces

   I.d. Guided waves along the fibers of a unidirectional fibre reinforced material

II. Through transmission using air-coupled and wideband transducers.

   II. a. Time domain analysis

.         II.a.1 Through transmission in flat surfaces

.         II.a.2 Through transmission in pipe walls

   II.b. Frequency domain analysis

.         II.b.1. C-Scans of the thickness resonances of FRP composite plates

III. Pulse-echo in steel plates and pipes.

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I. Generation and detection of guided waves in a solid using air-coupled and wideband piezoelectric transducers.

   I.a. Lamb waves in plates.

   I.b. Lamb waves in the FRP skin of sandwich structures

   I.b. Guided waves in the wall of a cylinder.

   I.c. Pseudo Lamb waves along curved surfaces

   I.d. Guided waves along the fibers of a unidirectional fibre reinforced material

.                Transducers: 250 kHz, wide-band

.                 Pulser-receiver: Olympus 5077

.                 Sample: Biofibers of Phormium tenax

Exprimental set-up

Received A-scans. Visualization of the propagation along the fibres by

changing the distance travelled by moving Rx transducers along fibre direction

II. Through transmission using air-coupled and wideband transducers.

   II. a. Time domain analysis

.            II.a.1 Through transmission in flat surfaces

.                 Samples: CFR plate and sandwich structure with nomex core and CFRP skin

.                 Transducers: 250 kHz, air-coupled and focused.

.                  Electronics: Panametrics (Olympus) 5077 Pulser receiver or Dasel Ultrascope.

CFRP layered and CFRP honeycomb plates

C-Scans

CFRP layered C-SCANS (Click on the image for futher information about the technique)

C-SCAN of CFRP honeycomb plate