Nondestructive Evaluation of Creep Damage Materials by using Ultrasonic Spectrum Analysis

초음파 Spectrum 해석에 의한 Creep 손상재의 비파괴평가

Nondestructive evaluation study was made on creep damage materials by ultrasonic spectrum analysis. The evaluation methods was developed in order to predict the change of ultrasonic attenuation with increasing creep damage. A new algorithm for the improvement of measuring accuracy of ultrasonic attenuation using a spectrum analysis has been developed. Normally, the ultrasonic attenuation is evaluated from 1st and 2nd peak values of the pulse-echo ultrasonic wave. The algorithm developed is incorporated in a measuring system which consists of a personal computer with ultrasonic apparatus and a digital storage oscilloscope. By the spectrum analysis method, it become popssible to describe approximately the attenuation change with increassing creep damage in Cr-Mo-V forging.