Journal of Power System Engineering (동력기계공학회지)

The Korean Society for Power System Engineering (한국동력기계공학회)
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Effect of Crack Orientation on Spatial Randomness of Fatigue Crack Growth Rate in FSWed 7075-T651 Aluminum Alloy Joints

마찰교반용접된 7075-T651 알루미늄 합금 용접부의 피로균열전파율의 공간적 변동성에 미치는 균열 방향의 영향

  • Jeong, Yeui-Han (Department of Mechanical Design Engineering, Pukyong National University) ;
  • Kim, Seon-Jin (Department of Mechanical & Automotive Engineering, Pukyong National University)
  • 정의한 (부경대학교 기계설계공학과) ;
  • 김선진 (부경대학교 기계자동차공학과)
  • Received : 2013.07.30
  • Accepted : 2013.09.11
  • Published : 2014.02.28
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Abstract

In this investigation, the effect of crack orientation on spatial randomness of fatigue crack growth rate (FCGR) in friction stir welded (FSWed) 7075-T651 aluminum alloy joints has been statistically analyzed by Weibull distribution. The fatigue crack growth tests are conducted under three different constant stress intensity factor range (SIFR) control at room temperature with R = 0.1 and frequency 10Hz on compact tension (CT) specimen machined at base metal (BM) and weld metal (WM). The experimental fatigue crack growth rate data were obtained for two types of specimens having LT and TL orientations. LT specimens both base metal and weld metal showed higher fatigue crack growth rate as compared to TL specimens. In the lower SIFR region, FCGR were found to be almost 3 times higher in higher SIFR region. The shape parameter of Weibull both LT and TL orientation for FCGR was increased with increasing SIFR, the scale parameter was also increased with increasing SIFR. The smallest value of the shape parameter was shown in weld metal specimens having LT orientation at lower SIFR region.

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References

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