We study subcritical fracture driven by thermally activated damage accumulation in the framework of fiber bundle models. We show that in the presence of stress inhomogeneities, thermally activated cracking results in an anomalous size effect; i.e., the average lifetime tf decreases as a power law of the system size tf ∼L-z, where the exponent z depends on the external load σ and on the temperature T in the form z∼f(σ/T3/2). We propose a modified form of the Arrhenius law which provides a comprehensive description of thermally activated breakdown. Thermal fluctuations trigger bursts of breakings which have a power law size distribution. © 2008 The American Physical Society.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUK-I1-005-04
Acknowledgements: We thank the Supercomputer Center of the Institute of Solid State Physics, University of Tokyo for the use of their facilities. N. Y. was supported by the 21st Century COE Program Applied Physics on Strong Correlation. F. K. was supported by the OTKA T049209. This work is supported by the JSPS ( No. 19340110) and the Global Research Partnership of KAUST (KUK-I1-005-04).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.