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

The Korean Society of Mechanical Engineers (대한기계학회)
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Influence of Stress Ratio of Elastic Waves Generated by Fatigue Crack Growth and Penetration in 6061 Aluminum Plates

6061알루미늄의 피로 균열 성장과 관통에 따른 탄성파의 응력비 영향

  • 안석환 (부경대학교 기계공학부) ;
  • 김진욱 (한국기계연구원 공인시험평가부) ;
  • 남기우 (부경대학교 신소재공학부)
  • Published : 2005.06.01
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Abstract

The characteristics of elastic waves emanating from crack initiation and propagation in 6061 aluminum alloy subjected to fatigue loading with different stress ratio was investigated. The objective of this study is to determine the properties of the signals generated from each stage of fatigue crack growth. AS a crack propagates, substantial elastic wave occurred just prior to penetration. Then it decreased and the crack penetrated. The waveforms and their power spectra were found to be dependent on the different stress ratio associated with the signals. It is determined that high-frequency signal $0.5{\sim}0.75$ MHz is most likely emitted during crack propagation at peak load of fatigue cycle which release the highest energy. It is determined that 0.3 MHz is closely related to crack closure effect. The frequency peaks below 0.25 MHz may be attributed to fretting or hydraulic noise.

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References

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