With the ultrasonic test inside material defects such as cracks, voids or separations are made visible.
The ultrasonic test is e.g.: used in welds, forgings, tubes and pressure vessels. The test material has to be sound conductive.
An acoustic pulse is given into the material by a transmitter / receiver probe. Flaws in the material reflect sound due to their wall. The reflections are recorded and displayed in an ultrasonic image.