Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Evaluation of Corrosion Degradation Characteristics of Turbine Blade Material Using Backward Radiated Ultrasound

후방복사된 초음파를 이용한 터빈 블레이드 재료의 부식 열화특성 평가

  • 송성진 (성균관대학교 기계공학부) ;
  • 김영환 (성균관대학교 기계공학부) ;
  • 배동호 (성균관대학교 기계공학부) ;
  • 정민호 (한국가스안전공사 가스안전시험연구원) ;
  • 권성덕 (안동대학교 물리학과)
  • Published : 2002.11.01
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Abstract

The corrosion degradation characteristics of the 12Cr alloy steel, which is widely used in fossil power plants as a turbine blade material, are evaluated nondestructively by use of the backward radiated Rayleigh surface wave. In order to evaluate corrosion degradation characteristics, we constructed automated system for the backward radiation, and the frequency dependency of the Rayleigh surface wave is investigated indirectly by measuring the angular dependency of the backward radiation of the incident ultrasonic wave in the specimens. The velocity of the surface wave decrease as the increase of the aging time in the backward radiation profile, which seems to result from the increase of the effective degrading layer thickness. And, amplitude of the surface wave increase as the aging time, which seems to result from the increase of the intergranular corrosion. The result observed in this study demonstrates high potential of the backward radiated ultrasound as a tool for the nondestructive evaluation of the corrosion degradation characteristics of the aged materials.

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References

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