Finite Element Analysis of Bending Zone Damage and Springback Behavior After V Bending Process of AA5754 Alloy

Abstract

Damages occurring in the bending area of the bent parts and the springback that occurs after shaping are among the important factors affecting the quality of the shaped products. In this study, the formability of AA5754 sheet metal with V bending at room temperature was investigated using finite element analysis. In the study, 4 different die angles (α) (60°, 90°, 120°, 150°), 3 different punch radii (R) (2, 4, 6 mm), and 3 different bending lengths (w) (9.5 mm, 19 and 38 mm) were used. Finite element analyses were performed using 2 different ductile damage criteria (Johnson-Cook (JC) and forming limit diagram (FLD)) and without damage criteria (NDC). As a result of the analyses, considering the die angle, the greatest springback was seen in the 150° die, while the greatest bending zone damage was seen in the 60° die. The largest deformation occurred at small die angles. Again, considering the punch radius, the greatest bending zone damage was seen in R2, while the greatest springback was obtained in R6. The difference (l) between the expansion and contraction zones in the bending area is 0.256 mm in the 60° die and 0.083 mm in the 150° die. It was determined that the greatest damage occurred on the inner surface. The damage angle on the inner surface is 12.14° in the 60° die, and 1.24° in the 150° die. Considering the damage criteria used, the largest springback occurred in FLD and the smallest springback occurred in JC.

Keywords

• AA5754
• Finite element analysis
• Springback / Springforward
• V bending

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