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Updated: Jun 8, 2026
05:04
Determining the Mechanical Strength of Ultra-Fine-Grained Metals
Published on: November 22, 2021
Fracture toughness and maximum stress in a disordered lattice system
Chiyori Urabe1, Shinji Takesue
1Meiji Institute for Advanced Study of Mathematical Science, Meiji University, Kawasaki, Japan. chiyori@isc.meiji.ac.jp
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 28, 2010
Summary
Disorder increases fracture strength in elastic networks with large initial cracks. This study models how spring randomness and crack length affect material toughness and stress distribution.
Area of Science:
- Physics
- Materials Science
- Solid Mechanics
Background:
- Fracture strength is crucial for material integrity.
- Understanding disorder effects on material properties is an ongoing challenge.
- Previous models often simplify network structures and disorder types.
Purpose of the Study:
- To model and quantify the disorder-induced increase in fracture strength.
- To investigate the relationship between initial crack length and fracture behavior.
- To analyze the enhancement of stress intensity factor and fracture toughness.
Main Methods:
- Developed a two-dimensional elastic network model with an initial crack.
- Simulated springs with random hardness (hard or soft) connected to nearest neighbors.
- Applied a uniform force threshold for spring failure.
Main Results:
- Maximum stress in the disordered system increases with sufficiently large initial crack length.
- Established correlations between crack length, force distribution, and work done.
- Derived an enhancement in stress intensity factor and fracture toughness.
Conclusions:
- Disorder can significantly enhance fracture strength in elastic networks.
- Initial crack length is a critical parameter determining the effectiveness of disorder.
- The fracture process zone analysis provides insights into toughness enhancement mechanisms.
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