# Disorder is good for you: the influence of local disorder on strain localization and ductility of strain softening materials

## Abstract

We formulate a generic concept model for the deformation of a locally disordered, macroscopically homogeneous material which undergoes irreversible strain softening during plastic deformation. We investigate the influence of the degree of microstructural heterogeneity and disorder on strain localization (formation of a macroscopic shear band) in such materials. It is shown that increased microstructural heterogeneity delays strain localization and leads to an increase of the plastic regime in the macroscopic stress–strain curves. The evolving strain localization patterns are characterized.

### Keywords

Fracture Microstructures Inhomogeneous material Numerical algorithms Probability and statistics## Notes

### Acknowledgements

Financial support of the Hungarian Scientific Research Fund (OTKA) under contract number PD-105256 and of the European Commission under Grant Agreement No. CIG-321842 are also acknowledged. DT is supported by a One Year scholarship program sponsored by the Free State of Bavaria for graduates of Central, Eastern and Southeastern European states. PDI is also supported by the János Bolyai Scholarship of the Hungarian Academy of Sciences. MZ acknowledges financial support of DFG under Grant No. Za171/8-1.

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