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Updated: Jul 16, 2026
07:28
Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
Percolation of diffusional creep: a new universality class.
Ying Chen1, Christopher A Schuh
1Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Physical Review Letters
|March 16, 2007
Summary
This study reveals a new percolation threshold for diffusional creep in heterogeneous grain boundaries. The creep viscosity shows unique scaling behavior near this threshold, differing from standard models.
Area of Science:
- Materials Science
- Physics
- Network Science
Background:
- Diffusional creep, specifically Coble creep, is a key mechanism in materials deformation.
- Understanding creep behavior in heterogeneous grain boundary networks is crucial for predicting material properties.
- Grain boundary sliding significantly influences creep dynamics.
Purpose of the Study:
- To investigate the percolation aspects of diffusional Coble creep on heterogeneous grain boundary networks.
- To determine a novel percolation threshold for such systems.
- To analyze the scaling behavior of creep viscosity and force/flux distributions near the percolation threshold.
Main Methods:
- Modeling diffusional Coble creep on a honeycomb lattice with two types of randomly distributed grain boundaries.
- Calculating the percolation threshold (p(cc)).
- Analyzing the divergence of creep viscosity and the scaling of force and flux distributions using finite-size scaling.
Main Results:
- A novel percolation threshold, p(cc) = 0.5416 ± 0.0036, was identified for the honeycomb lattice.
- Creep viscosity diverges with unique power-law exponents (t=1.69±0.09, s=1.88±0.12), distinct from standard percolation models.
- Force and flux distributions exhibit finite-size scaling with new exponents at the percolation threshold.
Conclusions:
- The identified percolation threshold and unique scaling exponents highlight distinct behaviors in creep systems compared to standard percolation phenomena.
- The observed scaling arises from the coupled nature of force and flux balances within the heterogeneous network.
- This research provides new insights into the fundamental mechanisms governing creep in complex materials.
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