This study presents a numerical investigation of the crashworthiness performance of an automotive bumper beam integrated with crash boxes under multiple collision scenarios using ANSYS Explicit Dynamics. The analysis evaluates deformation, stress distribution, and energy absorption under realistic impact conditions. The bumper system consists of a curved hollow rectangular beam with symmetrically positioned square crash boxes based on practical automotive geometry. Two materials, Aluminium 6061-T6 and Automotive HSS 590 Steel, are examined to assess the influence of material properties on crash performance. Nonlinear behavior is modeled using multilinear isotropic hardening to capture plastic deformation during impact. Three collision cases are considered: (i) Repeated low-speed frontal impacts at 5 km/h and 10 km/h to simulate successive minor collisions. (ii) Frontal impact to represent direct crash conditions. (iii) Oblique impacts at 10° and 30°. A high-stiffness wall is used to approximate rigid body interaction. Results show that deformation, stress, and energy absorption vary significantly with material and loading conditions. Repeated impacts lead to progressive structural degradation, emphasizing the importance of residual crashworthiness. The comparative analysis highlights the trade-off between lightweight efficiency and structural strength in material selection. The study extends conventional single-impact approaches by incorporating repeated and oblique collisions, providing a more realistic evaluation framework for bumper systems. The findings support the design and optimization of automotive front- end structures with improved crash performance.

Keywords— Automobile; Bumper ; Impact Resistant; Oblique Collisions .