Journal of the Korean Society of Safety (한국안전학회지)

The Korean Society of Safety (한국안전학회)
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A Study on Evaluation of Crack Opening Point in Al 2024-T3 Material

Al 2024-T3재의 Crack Opening Point의 평가에 관한 연구

  • 최병기 (조선대학교 공과대학 기계공학과) ;
  • 장경천 (한국생산기술연구원)
  • Published : 2004.06.01
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Abstract

This paper aims to analyze fatigue fracture mechnisms with high strength aluminum alloys, which are widely used in vehicles or airplanes to prevent accidents. Usefulness of the crack opening point was proposed by using an effective stress intensity facor when evaluating the fatigue crack propagaion rate. Therefore an exact crack opening ratio can be measured for a more exact fatigue crack propagation rate. It is found that the fatigue crack propagation rate was valid within the range of experimentation as an effective stress intensity factor. Summarizing the results are as follows in this paper ; (1) It is found that the value of the crack opening ratio is constant at the rear of the specimen, U'=0.25 at the crack mouth and U'=0.45 at the crack tip, respectively regardless of the stress ratio. (2) The crack opening ratio is different according to measurement locations. The crack opening ratio value was measured at the crack mouth by a clip gage or measured behind the specimen by a strain gage. It is found that the crack opening ratio value is more accurate that any other measuring test for evaluating the crack propagation ratio test by effective stress intensity factor.

Keywords

References

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