title: Crack growth by surface diffusion in viscoelastic media.
abstract: We discuss steady state crack growth in the spirit of a free boundary problem. It turns out that mode I and mode III situations are very different from each other: In particular, mode III exhibits a pronounced transition towards unstable crack growth at higher driving forces, and the behavior close to the Griffith point is determined entirely through crack surface dissipation, whereas in mode I the fracture energy is renormalized due to a remaining finite viscous dissipation. Intermediate mixed-mode scenarios allow steady state crack growth with higher velocities than for pure mode I.
authors.affiliation: Institut für Festkörperforschung, Forschungszentrum Jülich, D-52425 Jülich, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Spatschek
authors.forename: E A
authors.initials: EA
authors.lastname: Brener
authors.forename: D
authors.initials: D
authors.lastname: Pilipenko