Local-induction-heating bending process of b1500hs thin-walled rectangular steel tubes: A simulation and experimental investigation

To lighten and stiffen the structural components used in automobile bodies, the variable curvature local-induction-heating bending forming (VC-LIHBF) technology was developed. How-ever, few studies have been conducted on the optimization of the structural and geometric parameters of the inductor and the parameters of the LIHBF process. This paper focuses on the improve-ment of the cross-sectional distortion and the forming limit of the thin-walled rectangular steel tubes (TWRSTs) without the mandrel support. In this work, a coupled thermo-mechanical finite element analysis (FEA) method is developed to investigate the structural and geometric parameters of the inductor and the deformation behavior during VC-LIHBF. The temperature distribution is calcu-lated by the electromagnetic and heat transfer analysis, and the stress distribution is obtained by the deformation analysis. Experiments were carried out to validate the reliability of the proposed finite element model (FEM). The results indicate that the forming quality of the TWRST is significantly affected by the structural and geometric parameters of the inductor, the feed rate of the tube, the push speed of the bending roller and the distance between the inductor and the bending roller. The appropriate inductor and process parameters for a B1500HS TWRST were determined. The findings of this study may provide important guidance for practical manufacturing via the LIHBF process.