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S. Seichter, V. Archodoulaki, T. Koch, W. Fidi, A. Holzner:
"The experimentally survey of the crack growth approach for the fatigue life estimation of application-relevant rubbers";
Talk: Polymer Processing Society Conference 2015, Graz; 2015-09-21 - 2015-09-25; in: "Regional Conference Polymer Processing Society Graz 2015", C. Holzer, S. Laske, M. Payer (ed.); Graz (2015), 208.

Due to its properties rubber is often used for applications where cyclic loading is applied. It is very important to know how long rubber parts can withstand those loadings and many different models [1] can be found to predict the fatigue life of rubber under cyclic loading.
The models can be categorised in two overall approaches which are the crack nucleation approach and the crack growth approach.
The later one explicitly considers the growth of pre-existing flaws. In 1964 Gent et al. [2] described a method to estimate the life time of rubber dumbbell specimen under uniaxial loading from the crack growth behaviour of tensile strips made of the same material. This relationship has been often used and slightly modified to give a better fit to the experimental data.
Two testing machines are used to verify the applicability of this model. An electrically driven machine is used to measure the fatigue life of rubber compounds. A hydraulic testing machine is used to measure crack growth behaviour and fatigue life under high loads.
For a better coherence between the fatigue life and crack growth measurements the same specimen shapes are used for both investigations.
In the present work the fatigue lives of two application-relevant rubber compounds are investigated containing SBR, NR and BR. The type and amount of polymers are the same in the compounds, but they contain different types and amount of carbon black.
With this set-up the estimation of fatigue life originally proposed by Gent et al. [2] is evaluated and analysed regarding the applicability on application-relevant rubber compounds. The most important drawbacks are identified.
[1] Mars, W. V., Fatemi, A.. A literature survey on fatigue analysis approaches for rubber, International Journal of Fatigue, 2002, 24, 949-961
[2] Gent, A., Lindley, P. B., Thomas, A. G., Cut Growth and Fatigue of Rubbers. I. The Relationship between Cut Growth and Fatigue, Journal of Applied Polymer Science, 1964, 8, 455-466

uniaxial fatigue life, crack growth, industrial rubber