In fatigue fracture the crack growth is slow and in many materials exhibits apparent self-similarity as expressed by the dependence of the growth velocity on a stress intensity factor that grows with the crack size. We study the intermittency of fatigue crack dynamics in aluminium alloys by optical tracking. A power-law distribution of crack tip jumps is found with an exponent close to two and a cutoff which increases with time or crack propagation. The cutoff is related to the crack velocity. We show how such a distribution evolves or coarse grains with the scale of observation or time window. The correlations of the crack propagation imply short-range memory effects in the underlying dynamics. Our results show universal features of fatigue cracks and how these lead to the crack growth and failure in material samples.
CITATION STYLE
Lomakin, I. V., Mäkinen, T., Widell, K., Savolainen, J., Coffeng, S., Koivisto, J., & Alava, M. J. (2021). Fatigue crack growth in an aluminum alloy: Avalanches and coarse graining to growth laws. Physical Review Research, 3(4). https://doi.org/10.1103/PhysRevResearch.3.L042029
Mendeley helps you to discover research relevant for your work.