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Numerical Evaluation of Hemming Defects Found on Automotive Door Panels

유한요소해석에 의한 자동차 도어패널의 헤밍 결함 평가

Seo, O.S;Jeon, K.Y;Rhie, C.H;Kim, H.Y
서오석;전강윤;이철홍;김헌영

  • Received : 2015.04.07
  • Accepted : 2015.05.04
  • Published : 2015.08.01

Abstract

Hemming is used to connect two sheet metal components by folding the edge of an outer panel around an inner panel to create a smooth edge. The minimization of hemming defects is critical to the final quality of automobile products because hemming is one of the last operations during fabrication. Designing the hemmed part is not easy and is influenced by the geometry of the bent part. Therefore, the main problem for automotive parts is dimensional accuracy since formed products often deviate geometrically due to large springback. Few numerical approaches using 3-dimensional finite element model have been applied to hemming due to the small element size which is needed to properly capture the bending behavior of the sheet around small die corner and the comparatively big size of automotive opening parts, such as doors, hoods and deck lids. The current study concentrates on the 3-dimensional numerical simulation of hemming for an automotive door. The relationship between the design parameters of the hemming operation and the height difference defect is shown. Quality improvement of the automotive door can be increased through the study of model parameters.

Keywords

Hemming;Pre-hemming;Main-hemming;Height Difference;Springback;Numerical Analysis

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