Interfacial crack front wandering: influence of quenched noise correlations

We discuss the influence of spatially correlated quenched noise on the wand ering exponent of the crack-front line during slow in-plane crack propagati on. For a unifonn noise, the wandering exponent in the stastically stationa ry regime is zeta = 0.35 +/- 0.02, while the dynamic exponent is z = 0.75 /- 0.02. For short-range Gaussian correlations, the wandering expellent is shown to be zeta = 0.50 +/- 0.03 in the small fluctuation limit and zeta = 0.35 +/- 0.02 in the large fluctuation limit which can be shown to be consi stent with the uniform case. In the case of long-range correlations, charac terized by a self-affine exponent zeta(t), the wandering exponent is shown to scale as zeta = zeta(t) + 1 for a wide range of zeta(t) 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. (C) 1999 Elsevier Science B.V. All rights reserved.