표면SH파를 이용한 2.25Cr-1Mo강의 열화.손상 평가

Nondestructive Evaluation for Degraded 2.25Cr-1Mo Steel though Surface SH-wave

  • 김현묵 (서울산업대학교 비파괴평가기술연구소) ;
  • 박익근 (서울산업대학교 비파괴평가기술연구소) ;
  • 박은수 (서울산업대학교 비파괴평가기술연구소) ;
  • 안형근 (서울산업대학교 비파괴평가기술연구소) ;
  • 김정석 (서울산업대학교 비파괴평가기술연구소)
  • 발행 : 2000.11.02

초록

It is very important to evaluate the surface or subsurface microstructure because of their influences on mechanical properties of materials. Surface SH-wave which is horizontally polarized shear wave traveling along near surface and subsurface layer is an attractive technique for material evaluation. The destructive method is widely used for the estimation of material degradation but it has a great difficulty in preparing specimens from in-service industrial facilities. In this study, nondestructive evaluation for degraded structural materials used at high temperature though surface SH-wave method is discussed. 2.25Cr-1Mo steel specimens which were prepared by the isothermal aging heat treatment at $650^{\circ}$ were evaluated though ultrasonic nondestructive evaluation techniques investigating the change of sound velocity, attenuation coefficient and amplitude spectra. In addition, it has verified experimentally the frequency-dependence of attenuation coefficient though wavelet analysis method.

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