Increasing the Dimensional Accuracy of U-Bend Product of High Strength Steel Sheets by Pressure Pad

Abstract:

To reduce springback in U-shape of high strength steel sheet, the present paper proposes a new process parameter in U-bending technique. This paper aims to present the effect of clearance between die and pressure pad on springback behavior. The process in this work consists of four steps: (1) clamping of a sheet between a punch and a pressure pad, (2) bending with constant clamping force, (3) pushing-up at bottom of the part by using the pressure pad, and (4) final release tool. From the experimental results, decreasing of bending moment by bottom pushing-up resulted in the springback reduction. An appropriate of the clearance between die and pressure pad combined with bottom pushing-up force can be reduced springback. Our results suggested that the Y-U model, an advanced kinematic hardening, is essential for accurate numerical simulation of springback behavior.

• Periodical: Materials Science Forum (Volume 962)
• Pages: 159-166
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.962.159
• Online since: July 2019
• Authors: Pongsakorn Leetrakul, Komgrit Lawanwong*
• Keywords: High Strength Steel Sheet, Pressure Pad, Springback, U-Benging

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