Thermomecanical Design in the Automotive Industry

The thermomechanical fatigue assessment in the automotive industry is discussed. The design strategy is based upon a consistent approach of the thermomechanical loading, the mechanical constitutive law of the material, the damage parameters and the fatigue strength criteria. The good understanding of these different steps allows to perform predictive calculations of automotive parts subjected to thermomechanical loading. The main hypotheses and modeling choices are presented and results are illustrated by a series of computations on real 3D structures. Cracked area and lifetime prediction are described in the case of aluminum alloy cylinder heads submitted to transient thermal loadings.