Nonlocal approach to fatigue analysis of a welded bicycle frame joint

The paper attempts to predict the probabilistic fatigue strength scatter bands of a welded bicycle frame joint. The experimental data of the base material and the weld material were approximated by a nonlinear probabilistic model of the Weibull distribution. The fatigue strength for the material at the fatigue crack location was estimated considering the mean stress, residual stress, fatigue notch factor, and hardness profile. The output finite element numerical data of the real welded joint were compared with a nonlocal multiaxial fatigue criterion. The implementation of the volumetric method takes into account the stress gradient effect in the three‐dimensional geometry of the weld toe. The comparative localization of the minimum stress and the real crack indicates the validity of the numerical model. The predicted fatigue strength determines the possible failure of a welded joint at 5·105 cycles. Highlights The P–S–N curves are obtained for miniature specimens of the base and weld material. The Crossland equivalent stress distribution is averaged over a curvilinear weld toe. The failure probability is predicted for a welded bicycle frame joint.