Ultrasonic Attenuation Nondestructive Materials Characterization

Abstract

The present paper will present an overview of the current state-of-the-art of the use of ultrasonic attenuation as a nondestructive technique for materiales characterization. Examples will be given as to how proper choice of experimental parameters permit ultrasonic attenuation measurements to be used to study grain size, plastic deformation, and impurity concentration. Some comments will be made as to new techniques using laser beam generation and detection which afford the possibility of making ultrasonic attenuation measurements not possible by more conventional means and thereby expanding the practical usefulness of ultrasonic attenuation non-destructive materials characterization

Ultrasonic Attenuation as a Trace of Growth of Fatigue Crack in Steels

“…Under an applied stress the dislocation can break away from pinning points; then the length of the free loop extends to the full network loop length Ln of the dislocation. Then a .. k I(cr) A L~ (2) where I(cr) is the fraction of dislocation depinning. Ultrasonic attenuation of pure metals during bias stress experiments has been discussed according to the above dislocation string model [10].…”

“…Zhengliang Pan * Institute of Metal Research Academia Sinica Shenyang, CHINA Two comprehensive overviews on ultrasonic quantitative nondestructive evaluation and materials characterization were recently given by Thompson [1] and Green [2] respectively. Ultrasonic attenuation measurements are used to study a great variety of material microstructures and associated mechanical properties.…”