Fracture Roughness Scaling: a case study on planar cracks

Stéphane Santucci (1) , Mélanie Grob (2) , Alex Hansen (3) , Renaud Toussaint (4) , Jean Schmittbuhl (4) , Knut Jørgen Måløy (1)

1 Department of Physics [Oslo]
2 IPGS - Institut de physique du globe de Strasbourg
3 FAST - Fluides, automatique, systèmes thermiques
4 IPGS-GE - Géophysique expérimentale (IPGS)

Using a multi-resolution technique, we analyze large in-plane fracture fronts moving slowly between two sintered Plexiglas plates. We find that the roughness of the front exhibits two distinct regimes separated by a crossover length scale $\delta^*$. Below $\delta^*$, we observe a multi-affine regime and the measured roughness exponent $\zeta_{\parallel}^{-} = 0.60\pm 0.05$ is in agreement with the coalescence model. Above $\delta^*$, the fronts are mono-affine, characterized by a roughness exponent $\zeta_{\parallel}^{+} = 0.35\pm0.05$, consistent with the fluctuating line model. We relate the crossover length scale to fluctuations in fracture toughness and the stress intensity factor.

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Mécanique statistique [cond-mat.stat-mech]

Stéphane Santucci, Mélanie Grob, Alex Hansen, Renaud Toussaint, Jean Schmittbuhl, et al.. Fracture Roughness Scaling: a case study on planar cracks. EPL - Europhysics Letters, 2010, 92 (4), pp.44001. ⟨10.1209/0295-5075/92/44001⟩. ⟨hal-00640525⟩