The fractal growth of fatigue defects in materials
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Material defects growing during fatigue or damage process are described in terms of fractals. The assumed, uniform energy distribution over fractal defects corresponds to generalized energy density, treated as material characteristics. It has been shown that the way of evolution as well as the main features of an irreversible process are determined by characteristic (for a given material) fractal measures. The macroscopic range of length scales has been introduced via additional energy dependence upon macroscopic volume limiting defects evolution. Under certain constrains imposed upon defects growth, the effect similar to phase transition can be observed. The transition point coincides with the singularity of characteristic measures. In turn, the singularity comes from macroscopic limitations of defects growth. Theoretical results are compared with numerical simulations of the simplified stochastic fibre break process in composites. The simplified model has been generated in a way allowing to exclude heat outflow from the simulated system. This makes possible to examine defects growth over full range of scales beginning with the microscopic level. The calculated singularity appears at percolation point when observed correlated defects approach macroscopic size in accordance with the proposed theoretical model.
Key words: Fatigue process, fractal defects theory, numerical simulations.
- Bažant, Z. P. (1997) Scaling of Quasibrittle Fracture: Asymptotic Analysis. International Journal of Fracture 83: pp. 19-40
- Bažant, Z. P. (1997) Scaling of Quasibrittle Fracture: Hypothesis of Invasive and Lacunar Fractality, Their Critique and Weibull Connection. International Journal of Fracture 83: pp. 41-65
- Bažant, Z., Planas, J. (1998) Fracture and size effect. CRC Press, Boca Raton
- Carpinteri, A., Chiaia, B. (1996) Power Scaling Laws and Dimensional Transitions in Solid Mechanics 7: pp. 1343-1364
- Datta, D., Munshi, P., Kishore, N. N. (1996) Automated Utrasonic NDE of Composite Specimens by Cluster and Fractal Analysis. Nondestr. Test. Eval. 13: pp. 15-30
- Falconer, K. (1990) Fractal geometry. John Wiley & Sons, Chichester, New York
- Gandmaher, F. R. (1988). Matrix theory, Nauka, Moscow (in Russian).
- Goldsztein, R. W. and Mosolov, A. B. (1991). Cracks with fractal surfaces, WAN SSSR, 319 Nr 4 (in Russian).
- Goldsztein, R. W. and Mosolov, A. B. (1992). Fractal cracks, PMM. 56 (in Russian).
- Kasprzak, W., Lysik, B., Rybaczuk, M. (1990) Dimensional Analysis in the Identification of Mathematical Models. World Scientific, Singapore New Jersey
- Kohomoto, M. (1988) Entropy Function for Multifractals. Phys. Rev. A37: pp. 1345-1350
- Nottale, L. (1996) Scale, Relativity and Fractal Space- Time: Applications to Quantum Physics, Cosmology and Chaotic Systems 7: pp. 877-938
- Rybaczuk, M. (1992). The Fatigue Evolution of Fractal Defects in Metals (Edited by K. T. Rie), proceedings of Third International Conference on Low Cycle Fatigue and Elasto-Plastic Behavior of Materials, Elsevier London and New York.
- Rybaczuk, M. (1997). The Fractal Model of Defects Growth in Solids (Edited by R. C. Tennyson, A. E. Kiv), Computer Modelling of Electronic and Atomic Processes in Solids, Kluwer Academic Publishers, 309–320.
- Stoppel, P. (1999). Simulations of Fibres Breaking in the Stochastic Model of Composite, unpublished thesis (in Polish).
- Stoppel, P., Rybaczuk, M. In: Karihaloo, B. L., Mai, Y.-W., Ripley, M. I., Richie, R. O. eds. (1997) Simulations of Random Fractal Fiber Breaking in Composites. Advances in Fracture Research (ICF9), Amsterdam, Oxford, Pergamon, pp. 849-856
- Volterra, V., Hostinsky, B. (1938) Opérations Infinitésimales linéares. Herman, Paris
- The fractal growth of fatigue defects in materials
International Journal of Fracture
Volume 103, Issue 1 , pp 71-94
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- 1. Institute of Materials Science and Applied Mechanics, Wrocław University of Technology, Wyb. Wyspiańskiego 27, 50–370, Wrocław, Poland
- 2. Institute of Materials Science and Applied Mechanics, Wrocław University of Technology, Wyb. Wyspiańskiego 27, 50–370, Wrocław, Poland