Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Fatigue Crack Closure and Propagation Behavior Under Mixed-Mode Loading Observed by the Direct Measuring Method

직접측정법을 이용한 혼합모드 하중 하에서 피로균열의 닫힘과 전파거동

  • 송삼홍 (고려대학교 공과대학 기계공학과) ;
  • 서기정 (고려대학교 대학원 기계공학과) ;
  • 이정무 (고려대학교 공학기술 연구소)
  • Published : 2005.06.01
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Abstract

The stress conditions acting on the practical structure are complex, and thus most cracks existing in the practical structures are under mixed-mode loading conditions. The effect of shear load component of mixed-mode loading acts more greatly in the stage of crack initiation and initial propagation than crack propagation stage. Hence, research on the behavior in the stage of crack initiation and initial propagation need to be examined in order to evaluate behavior of mixed-mode fatigue cracks. In this study, the crack tip displacement(CTD) was measured by using the direct measuring method(DMM). We examined the behavior at crack tip by determining crack opening load$(P_{op})$. From the test results, the propagation behavior of mixed-mode fatigue cracks was evaluated by considering mixed-mode crack closure. Also, we examined the characteristic of crack propagation under mixed-mode loading with crack propagation direction.

Keywords

References

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