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Springback tendency with the variable blank holding force in the drawing process of the UHSS  

Kwak, Jung-Hwan (H.I.T Automotive Co. Ltd)
Jung, Chul-Young (R&D Center Dawoo Industry Co. Ltd.)
Kim, Se-Ho (School of Mechanical Engineering, Daegu University)
Song, Jung-Han (Metal Forming R&D Group, KITECH)
Publication Information
Design & Manufacturing / v.12, no.3, 2018 , pp. 60-65 More about this Journal
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
Formability; Springback; UHSS(Ultra High Strength Steel); Variable Blank Holding Force(VBHF);
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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