Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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Springback tendency with the variable blank holding force in the drawing process of the UHSS

초고강도강판 드로잉 성형에서 가변 블랭크 홀딩력에 의한 스프링백 경향

  • 곽정환 (에이치아이티오토모티브(주)) ;
  • 정철영 (대우공업(주) 기술연구소) ;
  • 김세호 (대구대학교 기계공학부) ;
  • 송정한 (한국생산기술연구원 성형기술그룹)
  • Received : 2018.10.30
  • Accepted : 2018.12.01
  • Published : 2018.12.01
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Abstract

The production of the automotive parts with the ultra high strength steel usually involves large amount of springback as well as fracture during the cold stamping process. Variable blank holding force(VBHF) can be used as one of the effective process parameters to reduce the springback amount with achieving better condition of formability. In this paper, VBHF with respect to the punch stroke is applied to the stamping process of the front side rear lower member for reducing the springback amount. From the analyses with constant blank holding force(CBHF), 24 kinds of VBHF conditions are utilized to investigate the springback tendency. It is noted that springback can be effectively reduced when BHF is increased near the bottom dead center because VBHF provides the tensile force to the blank with an adequate level of deformation without fracture.

Keywords

References

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