ABSTRACT
Automotive rubber components such as engine mounts or vibration isolators are subjected to dynamic loading in service. Computation of their fatigue lives is necessary in order to assure their safety and reliability. When subjected to cyclic loading, rubbers exhibit an important stretch-induced stress-softening phenomenon known as the Mullins' effect. This stress-softening occurs mostly during the first few cycles, after which the response of the material is unchanged by additional reloading. A constitutive model is proposed for the description of the stabilized state of such a behaviour. Predicting fatigue life of rubber components relies on two main points: first, the description of the suitable cyclic behaviour and second, the determination of a lifetime criterion. This behaviour was assumed to be stabilized and to depend on the cyclic stretches in a finite number of material directions. This model was then shown to be relevant for the analysis of some uni-axial fatigue experiments, in particular for the description of the control type influence.
