Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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Finite element analysis of spring back caused by frictional force in area of flange in press bending process

프레스 벤딩 공정에서 플랜지부의 마찰력이 스프링백에 미치는 영향에 대한 해석적 고찰

  • Yun, Jae-Woong (Department of Mold & Die Engineering, Kongju National University) ;
  • Oh, Seung-Ho (Department of Mold & Die Engineering, Kongju National University) ;
  • Choi, Kye-Kwang (Department of Mold & Die Engineering, Kongju National University) ;
  • Lee, Chun-Kyu (Department of Mold & Die Engineering, Kongju National University)
  • 윤재웅 (공주대학교 금형설계공학과) ;
  • 오승호 (공주대학교 금형설계공학과) ;
  • 최계광 (공주대학교 금형설계공학과) ;
  • 이춘규 (공주대학교 금형설계공학과)
  • Received : 2021.06.17
  • Accepted : 2021.06.30
  • Published : 2021.06.30
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Abstract

Springback is an essential task to be solved in order to make high-precision products in sheet metal forming. In this study, materials with four different elastic regions were used. For the forming analysis, the change of springback caused by the frictional force generated in the flange part during hat shape forming was considered by using the AutoForm analysis program. Factors affecting frictional force were blank holder force, friction coefficient, bead R and bead height. As a result of the forming analysis, the springback increases as the material with a larger elastic region increases. In addition, as the frictional force of the flange part increased, the tensile force in the forming direction increased and the springback decreased. In particular, the blank holder force and friction coefficient had a great effect on springback in mild materials (DC04, Al6016), and the bead effectively affects all materials. Through this study, it was considered that the springback decreased as the material with a smaller elastic region and the tensile force in the forming direction increased.

Keywords

References

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