Ultrasonic Testing (UT)
Ultrasonic inspection is a nondestructive method in which beams of high-frequency sound waves are introduced into materials for the detection of subsurface flaws in the material. The sound waves travel through the material with some attendant loss of energy (attenuation) and are reflected at interfaces (cracks or flaws). The reflected beam is displayed and then analyzed to define the presence and location of flaws or discontinuities.
The most commonly used ultrasonic testing technique is pulse echo, wherein sound is introduced into a test object and reflections (echoes) are returned to a receiver from internal imperfections or from the part's geometrical surfaces.
Applications include inspections for voids, cracks, and laminations, inspections of welds and thickness measurements.