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Reliable numerical fatigue life analyses are becoming increasingly important given the need to reduce the time and costs for product development and the need to evaluate large and single components. Stress-based approaches as well as the local strain approach and its fracture mechanics based extension (PJ model) are in use for that. Both the local strain approach and the PJ model require the supply of pure material data. This requirement for input data that are not component-specific makes such approaches interesting for widespread application. The accuracy of numerical fatigue life analyses is an essential criterion for the acceptance and the spread in industrial application. In the local strain approach, accuracy is determined on one hand by the transferability of material data for the fatigue life analysis of components and on the other by the damage accumulation rule. In this paper, the local strain approach and the PJ model are used to analyse fatigue life under bo th constant and variable amplitude loading. These analyses are based on the experimental results obtained from tests of a commercial vehicle component made of nodular cast iron EN-GJS-400-15. Aspects of transferability and damage accumulation are considered. Results obtained from using an elastic-plastic fracture mechanics based approach to estimate a P SWT-N curve, taken into account the inhomogeneities in the microstructure of the cast iron, are also presented

Nowadays cast iron components are widely used in highly stressed structures. Component lifetime is strongly influenced by inhomogeneities caused by the material's microstructure and the manufacturing process (graphite particles, (micro-)shrinkage pores, inclusions). Inhomogeneities often act as a fatigue crack starter. Lifetime until failure may be divided into stages for crack initiation, short and long crack growth. Initiation of a crack of technical size (a 1mm) is often dominated by the growth of short cracks. The paper presents an approach to analyse the mechanically short fatigue crack growth based on elastic-plastic fracture mechanics considering the closure behaviour of short cracks. The effective J-integral range is used as a crack driving force. Finite element analysis results as well as analytical solutions to approximate the crack driving force are presented. The application of the approach is successfully demonstrated for cast iron material EN-GJS-400-18-L T using data from fatigue tests, microstructure and fracture surface analyses to assess the fatigue life

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