Utilizing the Finite Element Method (FEM), two evolving CAE methods have recently reached a high level of efficiency and accuracy to optimize the properties of components in respect of stiffness, stress level or fatigue resistance.
The first type of CAE-methods is a family of optimization methods known as (parameter-free) shape and topology optimization. Very remarkable and useful results can be generated with these methods to reach considerable stiffness increases or stress and weight reductions.
The second CAE-method is fatigue life prediction which gives reasonable accurate outputs for component life if input data like stress history and material properties are well known. State of the art algorithms and software can handle a combination of complex load histories, detailed material description and large FEM-data to give reliable results in short time.
It will be demonstrated, using test cases and real world components, that combining these two CAE-methods can significantly increase the optimization level in respect to lifetime or weight. In the case of combining topology optimization with fatigue life prediction, which is a rather new idea, it can be detected that both material type (brittle / ductile) and loading history often have a decisive influence on the resulting design of components. Compared to common usage of FEM-based optimization, higher savings of weight can be obtained by including fatigue life prediction.