Effect of Continuous Bending under Tension on Dual-Phase Steels

Abstract:

Lightweighting plays a critical role in reducing vehicle emissions, a major source of air pollution in the European Union. While weight reduction during the use phase is important, environmental impacts across production and end-of-life stages must also be considered. Advanced forming technologies enable the use of high-strength materials while maintaining formability and energy efficiency. Continuous-bending-under-tension (CBT) is a promising forming technique capable of inducing higher plastic deformation than conventional processes. In this study, CBT experiments were conducted on dual-phase 1000 low-yield (DP1000-LY) steel. The material was subjected to uniaxial tensile loading combined with cyclic bending through a moving three-roll system. The effects of key process parameters, bending depth and speed ratio between the bending assembly and tensile loading, were systematically investigated. The results show that lower bending depths allow greater total deformation before fracture and result in higher tensile forces. Higher speed ratios lead to earlier failure both during and after CBT processing. Hardness measurements indicate comparable surface hardness on both sides of the specimens, regardless of single or double roll contact. These findings contribute to a better understanding of CBT process parameters and support its potential application in lightweight automotive component manufacturing.

• Periodical: Solid State Phenomena (Volume 388)
• Pages: 237-243
• DOI: https://doi.org/10.4028/p-SrPnJ8
• Online since: April 2026
• Authors: Gabriela Vincze*, Ricardo C. Alves, Rafael Oliveira Santos, Marilena C. Vincze
• Keywords: Continuous Bending under Tension, Formability, Steel

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