Interfacial crack front wandering: influence of quenched noise correlations

We discuss the influence of spatially correlated noise on the wandering exponent of the crack-front line during slow in-plane crack propagation. For a uniform noise, the wandering exponent in the stastically stationary regime is .35±0.02, while the dynamic exponent is z=0.75±0.02. For short-range Gaussian correlations, the wandering exponent is shown to be .50±0.03 in the small fluctuation limit and .35±0.02 in the large fluctuation limit which can be shown to be consistent with the uniform case. In the case of long-range correlations, characterized by a self-affine exponent ζt, the wandering exponent is shown to scale as ζt+1 for a wide range of ζt between −1.0 and +1.0. These results are discussed with reference to recent experiments of slow in-plane crack propagation between two annealed Plexiglas blocks.