What does "echo amplitude" represent in ultrasonic testing?

Echo amplitude in ultrasonic testing is a critical parameter that indicates the strength of the reflected sound wave that corresponds to a flaw within a material. When an ultrasonic wave is transmitted into a test object, it travels through the material and encounters different interfaces such as boundaries between different materials or the presence of flaws. When the ultrasonic wave hits a flaw, a portion of the sound energy is reflected back to the transducer. The amplitude of this reflected signal—measured as echo amplitude—is directly related to the size, type, and characteristics of the flaw. A higher echo amplitude typically signifies a larger or more severe flaw, while a lower echo amplitude may suggest it is smaller or more benign.

Understanding echo amplitude is essential for interpreting the results of ultrasonic testing. It plays a pivotal role in determining not only the presence of flaws but also providing insight into their significance. Therefore, recognizing echo amplitude as the strength of the reflected sound wave corresponding to a flaw highlights its importance in the assessment of the integrity of materials being tested.