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The Rotary Draw Bending (RDB) process is widely used in industry for the precise forming of metallic tubes. However, springback after plastic deformation compromises dimensional accuracy, requiring careful compensation in tooling design and process parameters. With increasing demands for lightweight structures and complex geometries, optimising the bending process has also become crucial to improve the product quality and reduce material waste.
This thesis aims to characterise the springback behaviour and the elongation induced during the RDB process, in order to understand the factors influencing elastic recovery and strain distribution in the bent tube. Numerical simulations using finite element method in ABAQUS were carried out on metallic tubes made from different materials, with a focus on SS304, S235, Fe510, AL2017A and Ti 99.5. Additionally, a series of experimental tests were conducted using SS304 and S235 materials with thicknesses of 1.5 mm and 2 mm, in order to evaluate the influence of variables such as centerline radius (CLR), bending angle, and final elongation. It was concluded that the CLR has a significant impact on springback behaviour. The influence of tube thickness was analysed for 1 mm, 1.5 mm and 2 mm tubes numerically but only minor differences were observed - the maximum 0.86 mm between thicknesses for ∆CLR when using Al2017A, corresponding to an error of 3.87%.
Higher CLR values correspond to increased springback in radius, whereas lower CLR values result in greater springback in angle. This trend was seen in both numerical and experimental results, though there was a discrepancy in the magnitude of the results. This study enhances dimensional control in the RDB process by proposing data-driven guidelines based on experimental evidence and advanced modelling techniques.