What is the term used to describe the gradual loss of sonic energy as ultrasonic vibrations travel through a material?

The term that describes the gradual loss of sonic energy as ultrasonic vibrations travel through a material is "attenuation." This phenomenon is significant in ultrasonic testing as it impacts the intensity of the sound waves as they propagate through different media. Attenuation occurs due to various factors, including absorption, scattering, and reflection of the ultrasonic waves.

In the context of ultrasonic testing, understanding attenuation is crucial because it affects the ability to detect flaws or discontinuities within the material. As sound waves encounter different materials or imperfections, their energy diminishes over distance. High levels of attenuation can lead to challenges in accurately interpreting the data collected during testing, as less energy reaching the receiving sensor may result in weaker signals.

Other terms mentioned play different roles in the behavior of ultrasonic waves. Reflection deals with the bouncing back of waves when they hit a boundary, refraction refers to the change in direction of waves as they move from one medium to another, and diffraction describes the bending of waves around obstacles or through openings. Understanding these concepts helps differentiate them from attenuation, which specifically refers to the loss of energy.