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

The Korean Society of Mechanical Engineers (대한기계학회)
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AE Characteristics of Fatigue Crack Opening and Closure in SWS 490B and Al 7075-T6 Alloy

SWS 490B와 Al 7075-T6 합금의 피로균열 열림 및 닫힘시 음향방출 특성 분석

  • 윤동진 (한국표준과학연구원 비파괴계측그룹) ;
  • 정충재 (한국표준과학연구원 비파괴계측그룹) ;
  • 이승석 (한국표준과학연구원 비파괴계측그룹) ;
  • 원창환 (충남대학교 급속응고신소재연구소)
  • Published : 2003.06.01
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Abstract

The objective of this study is to investigate the effect of AE activities in the crack opening and closure during the fatigue test. The laboratory experiments for various materials and test conditions were carrie out to identify AE characteristics of fatigue crack propagation. Compact tension specimens of SWS 490B and Al 7075-T6 alloy were prepared for fatigue test. AE activities were analyzed based on the phase of the loading cycle. In case of SWS 490B, the most of AE was generated when the crack began opening and the crack closed fully, whereas a few in the full opening of the crack. On the other hand, in case of Al 7075-T6, a distinct AE activity was observed during crack opening process. AE activity in the peak loading of cycle was different with each specimen. However, in the same material, AE activity was not affected by the change of cyclic frequency (0.1, 0.2, 1.0 ㎐). It was found that AE activities during crack opening and closure depend on material properties such as micro-structure, yield strength and elongation.

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References

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