PSI - Issue 43

Lucie Malíková et al. / Procedia Structural Integrity 43 (2023) 264–269 Lucie Malíková et al. / Structural Integrity Procedia 00 (20 22) 000 – 000

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• Classical MTS criterion (when N = M = 1) predicts much higher crack deflection than multi-parameter MTS criterion. • Using more higher-order terms (for instance 6 or 10 in our case) of the Williams expansion gives nearly zero values of the crack deflection angle, i.e. the crack would not deflect from its original direction at all for all the crack lengths studied. • The radial distance from the crack tip, where the MTS criterion is applied, also influences the results. It holds that the larger r c , the smaller crack deflection angles. • An experimental campaign would help to better understand the behaviour of a crack influenced by a corrosion pit and to validate the results of the numerical simulations.

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(c) (d) Fig. 2. Angle of the further crack propagation direction obtained via generalized MTS criterion at various radial distances from the crack tip: (a) r c = 0.1 mm, (b) r c = 0.5 mm, (c) r c = 1.0 mm, (d) r c = 1.5 mm. 4. Summary The work deals with an analysis of the mutual interaction of an elliptical corrosion pit and an edge crack. A rectangular specimen with a perpendicular crack and a corrosion pit in its closest vicinity loaded via remote tensile stress is modelled numerically by means of finite elements. Because of the existence of the pit near the crack, the stress state at the crack tip is redistributed and more or less amount of mixed-mode conditions occurs. Thus, the crack can deflect during the propagation from its original direction. In this paper, the multi-parameter form of the MTS fracture criterion is applied to investigate the crack deflection angle for various crack lengths. A thorough discussion is presented on the results regarding the effects of individual parameters, such as the crack length, the number of the