Surface and slight sub-surface detection
This detection method uses high frequency sound waves, typically above 2MHz to pass through a material
A probe is used which contains a piezo electric crystal to transmit and receive ultrasonic pulses and display the signals on a cathode ray tube or digital display
The actual display relates to the time taken for the ultrasonic pulses to travel the distance to the interface and back
An interface could be the back of a plate material or a defect
For ultrasound to enter a material a couplant must be introduced between the probe and specimen
Rapid results
Both surface and sub-surface detection
Safe
Capable of measuring the depth of defects
May be battery powered
Portable
Trained and skilled operator required
Requires high operator skill
Good surface finish required
Defect identification & No permanent record
Couplant may contaminate & Calibration required
Ferritic Material (Mostly)
