Ultrasonic Flaw Detection

a group of flaw detection methods in which the penetrating power of elastic waves in the ultrasonic, and sometimes in the audible, frequency range is used. Ultrasonic flaw detection is one of the most versatile methods of nondestructive testing. The methods of ultrasonic flaw detection are used to detect surface and deep-seated defects, such as cracks, pits, and scales in metallic and nonmetallic materials, including welded and soldered joints and bonded laminated structures. They are also used to determine the corroded areas of metals and to measure the thickness of specimens by the resonance method. (See also and ACOUSTO-OPTICALIMAGING.)