Multifractal burst in the spatiotemporal dynamics of jerky flow.
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 spatiotemporal 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.
Bharathi
M S
MS
Materials Research Centre, Indian Institute of Science, Bangalore 560 012, India.
Lebyodkin
M
M
Ananthakrishna
G
G
Fressengeas
C
C
Kubin
L P
LP