Fatigue of elastomeric materials includes two basic approaches to characterising fatigue curves. The crack nucleation approach counts the number of cycles to base material failure, and the crack growth approach observes crack propagation from the initial macro-notch. In this work, it is shown that fatigue life curves can be better estimated when the dependence of initial crack size on loading is considered. A new geometry for planar tension grips was presented and used for fatigue tests, and the effects of crack angle on fatigue results were analysed. Simplifications in crack growth calculations were proposed. Fatigue tests were performed at different frequencies using dumbbell specimens. A numerical model was formulated to estimate the actual test temperature and isothermal fatigue curves.
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