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Study of Blank Thickness Optimization in Free Bulging for Maximizing Bulged Height

가스압력을 이용한 자유벌징에서 성형양 최대화를 위한 두께 분포 최적화

  • 유준태 (한국항공우주연구원 재료구조연구팀) ;
  • 윤종훈 (한국항공우주연구원 재료구조연구팀) ;
  • 이호성 (한국항공우주연구원 재료구조연구팀) ;
  • 윤성기 (한국과학기술원 기계공학과)
  • Received : 2014.04.15
  • Accepted : 2014.05.27
  • Published : 2014.08.01

Abstract

Thickness profiled blank is designed using optimization techniques for maximizing the bulged heights during the free bulging of Inconel 718. The thickness of the blank was described by the Bezier curve and the locations of the control points were used as the design variables for optimization. The maximization of the bulged heights within the limited strain range served as the objective function and constraints for optimization. The equivalent static loads method for non-linear static response structural optimization (ESLSO) was used and the result of the optimization revealed 22 increased bulged heights. A free bulging test using a blank with an optimized profile was conducted to verify the optimization process. The results were compared with those of numerical analysis in terms of bulged height and deformed shape.

Keywords

Blow Forming;Free Bulging;Hot Forming;Equivalent Static Load;Optimization

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