Energy landscape view of fracture and avalanches in disordered materials

Molecular simulations are carried out to probe how strain-induced changes in the energy landscape are related to fracture processes in disordered systems. The simulations address a two-dimensional system that consists of 9952 particles with a distribution of sizes, and the changes in the structure and properties with strain are determined with the system constrained to an energy minimum. As the system is strained, local minima of the energy landscape are found to flatten out and disappear, which causes discontinuous structural rearrangements. These structural rearrangements, which correspond to avalanche events, lead to void nucleation and crack growth in discrete steps.