Unique Optimization Approach of Axle Component and Its Weld Life Improvement

Axles are a prominent part of automotive design. Along with a power transmission and differential system, axles support a vehicle’s weight and road-load reactions. Axles carry different attachments such as brakes and suspensions using brackets. Welds play an important role in design and longevity of bracket assemblies. Welds can be susceptible to fractures caused by intrusions akin to cracks and/or discontinuities, compounded by stress concentration due to weld profile and welding processes. Additionally, the simultaneous optimization of both brackets and welds remains a challenge with limited available methods. While topography or shape optimization techniques can enhance bracket robustness by minimizing compliance as the objective, this approach might inadvertently elevate the likelihood of weld fracture if weld dimensions are not concurrently updated.

In this endeavor, compliance is used to improve weld life without affecting bracket robustness by using the Vertex Morphing optimization technique. Existing weld dimensions are kept intact. Structural Stress Method is one of the widely accepted method available to calculate weld fatigue life using nodal forces. These nodal forces are optimized to achieve a desired improvement. Optimized design demonstrates significant improvement in weld fatigue life without affecting bracket robustness. This method can be used in conjunction with other optimization techniques and can be leveraged in concept design as well.