Abstract
Analyses of fracture behavior in Cu single crystal are conducted. Changes of atoms near crack tip under mode I loading are simulated by means of Molecular Dynamics (MD) method. Results are compared with experiments of fatigue crack propagation in Cu single crystal. MD simulations can reproduce the phenomenon that fatigue crack in single crystal propagates by slipping only on the active slip plane which is characteristic of the crystal system, which is confirmed by SEM observation in the tests.
Changes of atoms under cyclic loading are also simulated. It is shown that MD simulation, even when 2-body potential function is used, can represent the irreversible changes of atoms (i. e., accumulation of damage), which is thought to be essential behavior in fatigue fracture.
From the results above, it can be said that MD method may be a useful tool for analyzing a microscopical mechanism of fracture, at least in metal.
