• 제목/요약/키워드: 미소원공선단

검색결과 2건 처리시간 0.017초

미소원공주위의 피로크랙발생전파 거동에 관한 연구 (Behavior of Initiation and Propagation of Fatigue Cracks around Microholes)

  • 송삼홍;오환석
    • 한국해양공학회지
    • /
    • 제1권2호
    • /
    • pp.74-82
    • /
    • 1987
  • This study has been made to investigate into the behavior of fatigue limit, of fatigue crack initiation, and of fatigue crack propagation under the condition of rotating bending stress; specifically on the independency of stress field as well as the crack behavior of surface micro hole defect, which is made artificially through the specimen. The results obtained can be summarized as followa; 1) For the single micro hole defect, initiation of fatigue crack is occurred at both tips of microhole defect simultaneosly along the slip which are produced in the range of maximum principal stress arround micro hole defect independent of the size of micro hole defect. 2) For the neighbored deuble micro hole defects with equal size, in the range ($\frac{L}{r}$)ratio $\gtrsim$ 3 defined as the size of micro hole defect(2r) to the distance between the centers of micro hole defects (2L), the crack behavior of the micro hole defects is same as single one. However, for the range of $\frac{L}{r}$<3, the interference effect becomes significant as the ratio approaches to 1.

  • PDF

微小圓孔 및 微小슬릿材의 疲勞크랙 傳播擧動 (Behavior of Fatigue Crack Propagation of Micro-Hole and Micro-Slit Specimensns - For High-Frequency Heat Treantment Specimens -)

  • 송삼홍;윤명진
    • 대한기계학회논문집
    • /
    • 제10권1호
    • /
    • pp.78-85
    • /
    • 1986
  • 본 연구에서는 결함재의 결함선단에 발생 전파하는 피로거동을 검토하기 위해서 미소원공과 미소슬릿을 가공하고, 이것들의 피로한도를 기준으로 해서 이들 결함의 형상이 피로크랙 전파특성에 미치는 영향을 상세히 고찰하고자 한다.