What is the function of sound velocity in ultrasonic testing?

In ultrasonic testing, sound velocity plays a crucial role in assessing defect size and type. The speed of sound through a particular medium is essential for interpreting the time it takes for an ultrasonic pulse to travel through the material, reflect off any internal features, and return to the transducer. By knowing the sound velocity in the tested material, technicians can accurately calculate the location and characteristics of detected defects based on the time-of-flight of the ultrasound.

The ability to calculate the depth of the material is directly related to sound velocity; however, the primary focus in this context is on how that information is then utilized to determine defect size and type. Sound velocity, along with the characteristics of the reflected signals, aids in the identification of whether a defect is a crack, void, or other discontinuity—this is crucial for understanding the integrity and reliability of the material being tested. Other options refer to uses of sound velocity in different contexts but do not directly address the fundamental purpose of determining defect characteristics in ultrasonic testing.