Journal of the Korea Institute of Military Science and Technology (한국군사과학기술학회지)

The Korea Institute of Military Science and Technology (한국군사과학기술학회)
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Crack Growth Retardation Effect and Metallographic Observation of Aluminum Alloy Plate with Pre-Indentation

예비압입에 의한 알루미늄 합금 판재의 균열성장 지연효과 및 금속조직 변화

  • 황정선 (공군사관학교 기계공학과) ;
  • 조환기 (공군사관학교 항공우주공학과) ;
  • 윤용인 (공군 항공기술연구소)
  • Published : 2003.12.01
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Abstract

Fatigue test is conducted to see the effect of pre-indentation on the fatigue crack retardation of Al5052-H18 plate. Metallographic observation is introduced to deduce the relationship between fatigue crack retardation and fracture appearance with indentation. The grain size of the specimen becomes smaller with the increase of indentation force and the plastic zone is formed with the decrease of grain size. The fatigue striations are appeared densely as the Indentation force becomes higher. Metallographic observation and fatigue test results show that the indentation force has the limited value in improving fatigue crack retardation. Important point to retard the fatigue crack growth is that the crack growth path should pass through the indented area.

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References

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