Dynamic fragmentation of a ring: predictable fragment mass distributions
S Levy1, J F Molinari, I Vicari
1LSMS-IIC-ENAC, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
This study models material decohesion in expanding rings using a finite element framework. Fragment mass distributions are generalized gamma, but heaviest fragments depend on material toughness, size, and loading rate.
Area of Science:
- Computational mechanics
- Materials science
- Fracture mechanics
Background:
- Material failure under stress is a critical area of study.
- Understanding fragmentation patterns is key to predicting material behavior.
- Previous models often simplify the complex physics of decohesion.
Purpose of the Study:
- To model material decohesion in a uniformly expanding ring.
- To analyze the resulting fragment mass distributions.
- To investigate the factors influencing the heaviest fragments.
Main Methods:
- Utilizing a finite element framework.
- Coupling the framework with cohesive elements for decohesion modeling.
- Analyzing average fragment mass, mass distribution, and heaviest fragments.
Main Results:
- Fragment mass distributions are consistently described by generalized gamma distributions.
- The distribution of the heaviest fragments is sensitive to model parameters.
- Key parameters influencing heaviest fragments include toughness, specimen size, and loading rate.
Conclusions:
- The generalized gamma distribution provides a robust model for fragment mass.
- Material properties and loading conditions significantly impact extreme fragment characteristics.
- This framework offers insights into predicting fragmentation in dynamic scenarios.
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