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Effect of Specimen Orientation on Fatigue Crack Growth Behavior in Friction Stir Welded Al7075-T651 Joints

마찰교반용접된 Al7075-T651 용접부의 피로균열전파 거동에 미치는 시험편 채취방향의 영향

  • Jeong, Yeui Han (Graduate School of Mechanical Design Engineering, Pukyong Nat'l Univ.) ;
  • Kim, Seon Jin (Dept. of Mechanical & Automotive Engineering, Pukyong Nat'l Univ.)
  • 정의한 (부경대학교 대학원 기계설계공학과) ;
  • 김선진 (부경대학교 기계자동차공학과)
  • Received : 2014.02.04
  • Accepted : 2014.08.18
  • Published : 2014.12.01

Abstract

The aim of this paper is to investigate the effects of crack orientation on fatigue crack growth behavior in friction stir welded (FSWed) Al 7075-T651. Fatigue crack growth testing was conducted on compact tension (CT) specimens machined from the friction stir welds and the base metal under constant stress intensity factor range control. Tests were performed with the crack propagating nominally perpendicular to the weld line (termed the TL specimen) and the crack propagating in a parallel direction of the weld line (termed the LT specimen), and with three different constant stress intensity factor ranges. Both these specimen orientations were found to have a considerable effect on the fatigue crack growth behavior. Paris's law was adopted for the analysis of experimental results; the exponent m of the WM-LT specimen was determined to be 3.56, which was the largest value in this experimental conditions.

Keywords

Fatigue Crack Growth;Friction Stir Welding;Specimen Orientation;Constant Stress Intensity Factor Range

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