A Study on the Optimization of Reinforcement Bead Geometry and Stiffness Enhancement in Automotive Body Structures Using Arc-Based Deposition

In response to the increasing structural mass of electric vehicles, there is a growing need for localized reinforcement strategies that can enhance local stiffness, defined as resistance to concentrated bending deformation, while minimizing thermal distortion and maintaining full compatibility with existing arc-based manufacturing systems. This study presents a reinforcement strategy using arc-based solid wire deposition, designed to improve local stiffness-defined as the resistance to localized bending deformation-while minimizing thermal distortion. Two bead geometries were developed: an S-shaped bead for flat regions to disperse stress through curved paths, and a GUSSET bead with weaving deposition to enhance stability in corner areas. Key process parameters, including weaving amplitude and frequency, were optimized to ensure consistent bead morphology and reduced heat input. Bending tests showed that the S-shaped design(SR) improved maximum load capacity by up to 49.6% compared to conventional Gird patterns (GR). Three-dimensional surface profile measurements verified the geometric consistency and low thermal-induced distortion of the optimized reinforcement beads across different clamping conditions, thereby demonstrating the practical viability of arc-based deposition for localized structural enhancement in automotive body applications.