Journal of Welding and Joining

The Korean Welding and Joining Society (대한용접접합학회)
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Bead Shape and Conditions of Friction Stir Processing to Improve Fatigue Strength

피로강도 향상을 위한 표면마찰교반법의 가공조건 및 비드형상

  • 박정웅 (조선대학교 토목공학과) ;
  • 안규백 (포스코 기술연구소 접합연구그룹) ;
  • 김흥주 (RIST 플랜트연구본부) ;
  • 조병철 (조선대학교 대학원 토목공학과)
  • Received : 2013.07.23
  • Accepted : 2013.08.07
  • Published : 2013.08.31
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Abstract

Burr grinding, Tungsten Inert Gas (TIG) dressing, ultrasonic impact treatment, and peening are used to improve fatigue life in steel structures. These methods improve the fatigue life of weld joints by hardening the weld toe, by improving the bead shape, and by creating the compressive residual stress. In this study, a new post-weld treatment method improving the weld bead shape and metal structure at the welding zone using Friction Stir Processing (FSP), a welding process, is proposed to enhance fatigue life. For that, a pin-shaped tool and processing condition employing Friction Stir Processing (FSP) is established through experiments. Experimental results revealed that fatigue life is improved by around 50% compared to as-welded fatigue specimens by reducing the stress concentration at the weld toe and by generating a metal structure finer than that of flux-cored arc welding (FCAW).

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References

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