2, Eötvös University, Budapest, , Hungary
The statistics and origin of intermittent micro-plasticity in a one and two dimensional dislocation dynamics simulation are studied via a linear stability analysis of the evolving dislocation configuration. When the spatial dimension is unity, a fold catastrophe is found to directly relate the dislocation configuration prior to loading to the stress at which the first plastic event occurs. More generally, it is found that the resulting plasticity of the first event is related to the eigenvector structure of the dynamical matrix evaluated at the emerging instability. Within this context the degree of micro-plastic localization and the system's closeness to criticality will be discussed.