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The problem of cracks in cylinder heads due to low cycle fatigue (thermal fatigue) is well known for engines with high specific power output. However it is still difficult to predict the lifetime of a new cylinder head due to the number of influencing parameters and the complexity of material behavior. Better understanding of cylinder head fatigue can improve the development process of a new engine concerning CAE as well as mechanical testing efficiency. Therefore a CAE tool which can calculate strains and stresses as a function of time for a defined operating cycle of the engine was developed. In parallel a measuring technique was developed which allows to measure strains on the surface of the combustion chamber side of the cylinder head during fired engine operation. For different Aluminum-Silicon casting alloys the material behavior was described in the Finite Element Program ABAQUS by a nonlinear kinematic / isotropic hardening model.

Modern passenger car engines are designed to operate at increasingly higher rated engine speeds with higher thermal loads. To reduce engine weight and length, the engines are usually siamesed without a cooling path between the cylinder liners. This leads to high temperatures in the siamesed area and to an increase in liner deformation. The distortion of the cylinder liners of internal combustion engines has a significant affect on engine operation. It can affect the oil consumption, the blow-by, the wear behavior and, due to friction, the fuel consumption. In order to achieve future requirements regarding exhaust emissions and fuel consumption, the development of low distortion engine blocks will play a significant role.