抄録
Since the soundness and life prediction methods of the material were important subjects in industry, ultrasonic spectroscopic non-destructive evaluation method on fatigue damage was proposed. In this method the velocity of an ultrasonic wave that propagated the material surface was measured, and then movable dislocation loop density was calculated using the measured velocity and also the area of slip bands that appeared in notch surface was measured. Then, as compared with the slip bands area method, validity of this method was examined. Since the results of the ultrasonic spectroscopy method and the slip bands area method were qualitatively agreed, it was clarified that this method was effective to evaluate the life prediction of metal materials.
