Fatigue life simulation of a rear tow hook assembly of a passenger car

A comparison between laboratory test data on fatigue crack nucleation in a rear tow hook pin assembly of passenger vehicle and a computational methodology using commercial package software is presented. Fatigue damage is determined using local material response, measured during experimental tests. Experiments were performed simulating the actual conditions in the customer environment. Stress and strain were experimentally measured by using strain gages, bonded on the hook assembly. These experimental lives are compared with those obtained through numerical analysis using a commercial fatigue software. Fatigue analysis methods (S–N curves, rainflow counting and Miner rule) were used to determine the fatigue damage imposed on the component. Interpretation and evaluation of the measured strain and stresses, simulation tests and fatigue life assessments, on the basis of S–N curve, are described in this paper.