Thermo-mechanical fatigue life assessment of aluminium components using the damage rate model of Sehitoglu

Different lifetime approaches were tested to fulfil the requirements for the fatigue analysis of engine components made of aluminium. Besides damage parameters and energy criteria, the complex damage rate model of Neu/Sehitoglu was evaluated. Approximately 20 parameters have to be determined to take into account damage due to mechanical fatigue, oxidation and creep. Many LCF- and TMF-tests, including experiments in argon atmosphere, were conducted to determine the parameters of the model. The different models are compared and the advantages for practical use are discussed. The model of Sehitoglu gives the best accuracy in the description of the experimental lifetime results. In contrast to various damage parameters, local in-phase TMF loading is taken into account properly.