PSI - Issue 5

Jürgen Bär et al. / Procedia Structural Integrity 5 (2017) 793–800 Jürgen Bär et al. / Structural Integrity Procedia 00 (2017) 000 – 000

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notch root requires an extension of the complete crack front (figure 7, right). As mentioned above, the crack propagation in the notch root is accelerated due to a notch stress concentration, whereas on the specimen surface only a slight notch-depended acceleration takes place. Accordingly, the crack propagation on the specimen surface retards the propagation along the notch root. This interdependency of the crack propagation in two main directions has to be considered in a mathematical model of 2-dimensional crack propagation to get a precise prediction of the crack propagation until the formation of a through-the-thickness crack front.

Fig. 7. Propagation of a quarter elliptical crack from the edge of the notch.

References

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