High silicon alloyed nodular cast iron consists of a purely ferritic matrix and graphite nodules, mainly. Varying wall thicknesses and manufacturing conditions result in different graphite morphologies throughout a structural component. From an experimental point of view, axial fatigue and tensile tests were carried out on specimens with differently degraded graphite. From a numerical point of view, the microstructure has been modelled using a finite element (FE) approach with representative volume elements (RVE). The RVE models were built according to micrographs of fatigue specimens. The generated RVEs determine effective material properties through elasto-plastic homogenization and were subsequently analysed using a shakedown approach. In shakedown theory, the material re-enters the elastic regime after a few cycles of initial plastic deformation. This work uses the shakedown theorem to derive a lower bound estimation of the endurance limit from a non-incremental simulation. Here, the material has to be modelled elastic-perfectly plastic. The major challenge in modelling nodular cast iron is to determine suitable material parameters for the graphite and ferrite phase, revealed by parameter studies on the static and cyclic model. By using reasonable material parameters, fundamental effects, observed in the fatigue tests, were reproduced on the model level.

So far, the influence of aging on the mechanical properties of ZnAlCu alloys has primarily been investigated under tensile load. Since some applications, such as plain bearings, are subjected to compressive loads, the results presented in the literature do not fully encompass all areas of application. Therefore, this publication focuses on the influence of artificial aging on the 0.2% compressive yield strength. Samples from ZnAl1Cu0.7, ZnAl11Cu0.7 and ZnAl11Cu2 were aged at different aging temperatures for up to 840 h. After different aging periods, compressive tests as well as microstructure investigations with SEM and XRD were carried out. Furthermore, the dimensional stability of ZnAl11Cu0.7 was investigated in a quenching dilatometer. Shrinkage of up to 0.08%, followed by swelling, was determined. Compressive tests revealed a decrease in the 0.2% compressive yield strength across all tested alloys, most pronounced at the beginning of the aging process, reaching an approximately constant strength level after an alloy- and temperature-dependent aging period. At the end, based on the results, a possible way to determine the constant strength level and the necessary aging time to reach this strength level for specific application temperatures is presented to ensure stable mechanical properties during operation.