PSI - Issue 5

Kaveh Samadian et al. / Procedia Structural Integrity 5 (2017) 1245–1252 Kaveh Samadian/ Structural Integrity Procedia 00 (2017) 000 – 000

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5. Conclusion

In this paper, approaches based on evaluating the strain patterns are introduced with the aim to investigate the interaction between non-co-planar flaws under plastic deformation. A rigorous analysis of the trajectory of bands of maximum equivalent strain, and the magnitude of strains along these bands, allows to clearly distinguish between cases of interacting and non-interacting flaws. Two alternative approaches are based on simple geometric characteristics of the bands of maximum strain: linear regression angle and degree of curvature. Both approaches reveal significant differences in the interaction as out-of-plane distance is changed. Three scenarios have been identified. For high out-of-plane distances, there is no interaction. As out-of-plane distance decreases, strain bands connect and create an interaction effect on crack driving force (reflected in an increase of strain levels along the bands). For very small out-of-plane distances, strain bands become curved, which hypothetically reveals an additional interaction effect on crack tip constraint.

Acknowledgment

The authors acknowledge the financial support from Ghent University through grant number BOF13/24J/122.

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