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Effect of Initial Crack Location on Spatial Randomness of Fatigue Crack Growth Resistance in Friction Stir Welded AA7075-T651 Plates

마찰교반용접된 AA7075-T651 판재의 피로균열전파저항의 공간적 불규칙성에 미치는 초기균열위치의 영향

  • Kim, Seon Jin (Dept. of Mechanical & Automotive Engineering, Pukyong Nat'l Univ.)
  • 김선진 (부경대학교 기계자동차공학과)
  • Received : 2014.06.05
  • Accepted : 2014.07.09
  • Published : 2014.09.01

Abstract

In the present paper, the effects of initial crack location on spatial randomness of fatigue crack growth resistance (FCGR) in friction stir welded (FSWed) AA7075-T651 plates were studied. The objective of this study is to characterize the statistical properties of FCGR for three different types of initial crack location (ICL) specimens. In this work, the FCGR coefficients were treated as a spatial random process. It was found that the FCGR coefficients for all initial crack location specimens closely followed a two parameter Weibull distribution. The shape parameter of the Weibull distribution for BM-ICL specimens showed the largest value of 7.50, and that for the WM-ICL specimens showed the smallest value of 2.61. In addition, the autocorrelation functions for all the ICL specimens followed the exponential function.

Keywords

Fatigue Crack Growth Resistance;Friction Stir Welding;Initial Crack Location;Spatial Randomness

Acknowledgement

Supported by : 부경대학교

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