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Predicting Catalyst Extrudate Breakage Based on the Modulus of Rupture
Published on: May 13, 2018
Discrepancy between subcritical and fast rupture roughness: a cumulant analysis.
N Mallick1, P-P Cortet, S Santucci
1Laboratoire de Physique, CNRS UMR 5672, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France.
Physical Review Letters
|August 7, 2007
Summary
Rough crack fronts in paper do not follow scaling laws. Analysis reveals distinct local roughness in slow versus fast growth regimes, challenging previous assumptions.
Area of Science:
- Physics
- Materials Science
Background:
- Crack propagation in materials is often idealized with scaling laws.
- Real-world cracks, like those in paper during creep, exhibit complex roughness.
- Understanding crack front dynamics is crucial for material failure analysis.
Purpose of the Study:
- To investigate whether rough crack fronts in paper during creep experiments adhere to true scaling laws.
- To quantify the local roughness of crack fronts using a novel method.
- To compare the roughness characteristics in different growth regimes.
Main Methods:
- Creep experiments on paper sheets to generate crack fronts.
- Estimation of local roughness exponents using the first-order cumulant.
- Analysis of a large dataset comprising 102 crack fronts.
Main Results:
- Rough crack fronts in paper do not exhibit true scaling behavior.
- A significant difference in local roughness was observed between slow (subcritical) and fast growth regimes.
- The first-order cumulant effectively characterizes local crack front roughness.
Conclusions:
- True scaling laws are not universally applicable to rough crack fronts in paper under creep conditions.
- Crack growth rate significantly influences the local roughness of the crack front.
- The findings provide new insights into the physics of fracture and material failure.
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