Oscillatory Fracture Paths in Thin Elastic Sheets:When geometry rules the fracture path

摘要

We report a novel mode of quasi-static oscillatory crack propagation when a cutting tool is driven through a thin polymer filmrn[6,7].In our experiments, for tools with a large enough width, the crack tip follows a highly periodic path, leaving behind arnstriking oscillatory pattern.Taking into account the separation of the film's bending and stretching energies and using classicalrnfracture theory, we propose a geometrical model that accurately reproduces the behavior observed experimentally.Numericalrnintegration of our geometrical rules accurately reproduces both the shape of the fracture pattern and the detailed timernevolution of the propagation of the crack tip [16].