Fatigue Crack Propagation of Super Duplex Stainless Steel and Time-Frequency Analysis of Acoustic Emission

수퍼 2상 스테인리스강의 피로균열 진전특성과 음향방출신호의 시간-주파수 해석

  • 이상기 (부경대학교 재료공학과 대학원) ;
  • 도재윤 (부산기능대학) ;
  • 남기우 (부경대학교 재료공학부) ;
  • 강창룡 (부경대학교 재료공학부)
  • Published : 2000.04.20

Abstract

On this study, the fatigue crack propagation of super duplex stainless steel is investigated in conditions of various volume fraction of austenite phase by changing heat treatment temperature. And we analysed acoustic emission signals during the fatigue test by time-frequency analysis methods. As the temperature of heat treatment increased, volume fraction of austenite decreased and coarse grain was obtained. The specimen heat treated at $1200^{\circ}C$ had longer fatigue life and slower rate of crack growth. As a result of time-frequency analyze of acoustic emission signals during fatigue test, main frequency was $200{\sim}300kHz$ having no correlation with heat treatment and crack length, and 500kHz was obtained by dimple and separate of inclusion

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