Abstract
The loads and the material response of a brake disc in the actual braking situation are complicated to analyse. In order to study thermomechanical fatigue, test specimens having controlled boundary conditions are regularly employed. In the present paper, results from analytical modeling, finite element modeling and experiments are analysed and compared for a constrained TMF test. Standard rheological material models, adapted to account for the tension-compression asymmetry with respect to yield for the studied gray cast iron, are used to study investigate the specific TMF test set-up. It is found that the stress evolution during testing can be well described using the studied models. Assessment of fatigue laws from the literature gives mixed results, highlighting the importance of finding damage parameters for the actual studied material.
KEYWORDS – disc braking, cast iron alloy, thermal stress, thermomechanical fatigue, analytical modelling, FE analysis, laboratory experiments