News

  • Posted on: 8 August 2015
  • By: Anonymous

Turbulent Fracture Surfaces: A Footprint of Damage Percolation?

We show that a length scale ξ can be extracted from the spatial correlations of the “steep cliffs” that appear on a fracture surface. Above ξ, the slope amplitudes are uncorrelated and the fracture surface is monoaffine. Below ξ, long-range spatial correlations lead to a multifractal behavior of the surface, reminiscent of turbulent flows. Our results support a unifying conjecture for the geometry of fracture surfaces: for scales larger than ξ, the surface is the trace left by an elastic line propagating in a random medium, while for scales smaller than ξ, the highly correlated patterns on the surface result from the merging of interacting damage cavities.

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Focus: Crack Patterns Resemble Fluid Turbulence

  • Posted on: 8 August 2015
  • By: Dinh Cong Minh
A statistical analysis of crack surfaces from three different materials reveals a deep connection with fluid turbulence and a potentially new approach to studying failed machine parts.
 
Figure caption
S. Vernède et al., Phys. Rev. Lett. (2015)

Topography of a crack. Fracture surface images processed to highlight the steepest cliffs of (left to right) aluminum, mortar, and ceramic in frames that are 3, 20, and 8mm wide, respectively. The steepest cliffs are white and appear to have a pattern rather than being entirely random.

Breakthrough in Quantitative Fractography

Tortoise unique technology extracts valuable mechanical properties from a scanned height map obtained from only a single fracture surface of small size.

Authors & Affiliations

Stéphane Vernède1, Laurent Ponson2,*, and Jean-Philippe Bouchaud3

  • 1Tortoise Analytics, 75005 Paris, France
  • 2Institut Jean le Rond d’Alembert (UMR 7190), CNRS-Université Pierre et Marie Curie, 75005 Paris, France
  • 3Capital Fund Management, 23 rue de l’Université, 75007 Paris, France