Glossary

Ultrasonic Testing (UT) is a non-destructive testing (NDT) method that relies on high-frequency sound waves—typically between 0.5 and 25 MHz—to evaluate materials without causing damage. A transducer generates ultrasonic waves that are directed into the test material, and whenever these waves encounter a boundary such as a crack, void, inclusion, or even the back wall of the material, part of the energy is reflected back. The reflected signals are captured by the same or a separate transducer and displayed on a screen, allowing technicians to determine the presence, size, and depth of internal flaws. This ability to “see” inside a material makes UT one of the most sensitive and widely used inspection methods for detecting cracks, porosity, inclusions, and other discontinuities that could compromise performance.

Beyond flaw detection, UT is also used to measure thickness—an essential function for monitoring corrosion in pipes, tanks, and pressure vessels—and for material characterization. Its applications span industries such as aerospace, automotive, construction, and energy, where precision and reliability are critical. UT offers several advantages: it is highly sensitive to small flaws deep within materials, provides accurate depth and dimensional information, and is portable and safe compared to radiation-based methods. These qualities make ultrasonic testing a vital quality-control tool for ensuring the integrity and safety of components in demanding industrial environments.