Topology-driven structural optimization and cross-material robustness assessment of automotive wheel rims using finite element analysis

This paper gives a combined approach to the structural optimization and finite element analysis of an automotive alloy wheel rim where the mass is to be minimized without compromising the structural integrity to the expected loads in the service. A three-dimensional finite element model was created to assess the distribution of the stresses, radial movement, and safety performance under standardized stressful conditions of the static load. Geometric optimization based on topology was then used to enhance the strength-to-weight ratio, and a multi-material sensitivity study conducted to determine the sensitivity of the optimized design when using materials with vastly different mechanical properties. Besides traditional lightweight alloys, high-strength materials such as Ti-6Al-4V and W-Ni-Fe were taken as cases of benchmarking in order to assess the material- geometry interaction. The optimal design resulted in a 7.20 kg to 6.10 kg (about 15.3 percent) mass reduction, a reduction in maximum von Mises stress by 420 to 355 Mpa and a radial displacement by 3.05 to 1.90 mm. The factor of safety increased to 1.50 as compared to 1.20, and fatigue endurance increased to 1.0× 106 cycles as compared to 2.0× 105 cycles. Numerical predictions were strongly agreed with by experimental validation with a maximum deviation of less than 3.5%. The results confirm the argument that topology optimization and cross-material sensitivity analysis can offer a sound and material-blind design methodology capable of maximizing the structural performance at the cost of manufacturability and safety thresholds. The technique results in a transferable design of advanced lightweight in vehicle structural components.