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Multifractal burst in the spatio-temporal dynamics of jerky flow

M. S. Bharathi·M. Lebyodkin·G. Ananthakrishna·C. Fressengeas·L. P. Kubin
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Abstract

The collective behavior of dislocations in jerky flow is studied in Al-Mg polycrystalline samples subjected to constant strain rate tests. Complementary dynamical, statistical and multifractal analyses are carried out on the stress-time series recorded during jerky flow to characterize the distinct spatio-temporal dynamical regimes. It is shown that the hopping type B and the propagating type A bands correspond to chaotic and self-organized critical states respectively. The crossover between these types of bands is identified by a large spread in the multifractal spectrum. These results are interpreted on the basis of competing scales and mechanisms.

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M. S. Bharathi, M. Lebyodkin, G. Ananthakrishna, C. Fressengeas, L. P. Kubin. 2001-09-11. Multifractal burst in the spatio-temporal dynamics of jerky flow. https://doi.org/10.1103/physrevlett.87.165508

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