PSI - Issue 33

Jesús Toribio et al. / Procedia Structural Integrity 33 (2021) 1197–1202 Jesús Toribio / Procedia Structural Integrity 00 (2021) 000–000

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Fig. 6. Fracture profile (notched sample 6C: 6 drawing steps & geometry C).

3. Artistic approach: proposing a link between fracture and structural integrity of cold drawn pearlitic steels and John Ford’s movies recorded in Monument Valley The afore-said fracture profiles given in Figs. 2-6 show evidence of notch-induced anisotropic fracture behaviour (very marked) in heavily cold drawn pearlitic steels, accompanied by crack path deflection (with high deflection angle close to 90º in relation to the transverse direction for mode I propagation). Such a deflection angle close to 90ª produces a sudden changes in the matter of crack paths, thereby creating a sort of vertical cracking wall or a kind of fracture propagation step . The appearance of such a wall (or step) requires, in addition to microstructural orientation (microstructural anisotropy), a certain degree of stress triaxiality (constraint) to be produced, as discussed recently by Toribio and Ayaso (2020). In case of a low level of triaxiality, the fracture step is less pronounced, or it is simply a fracture embryo, or even it disappears. In steels with an intermediate degree of drawing (Fig. 7) the anisotropic behaviour is not so pronounced, but it does happen in a more or less evidence manner shown in the beautiful fracture profile of Fig. 7 resembling John Ford’s movies and producing a kind of Monument Valley Profile (MVP), cf. Fig. 8.

Fig. 7. Fracture profile (notched sample 3B: 3 drawing steps & geometry B).