title: Crack street: the cycloidal wake of a cylinder tearing through a thin sheet.
abstract: When a cylindrical tool cuts through a thin sheet of a relatively brittle material, it leaves behind a visually arresting crack street in its wake, reminiscent of a vortex street in the wake of a cylinder moving through a fluid. We show that simple geometrical arguments based on the interplay of in-plane stretching and out-of-plane bending suffice to explain the cycloidal morphology of the curved crack. The coupling between geometry and dynamics also allows us to explain the "stick-slip"-like behavior of tearing and suggests that these oscillations should occur generically in the brittle fracture of thin solid films.
authors.affiliation: Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Ghatak
authors.forename: L
authors.initials: L
authors.lastname: Mahadevan
mesh_terms: D008422:Materials Testing / Q000379:methods*; D008962:Models, Theoretical; D011126:Polypropylenes / Q000737:chemistry
chemical_list: D011126:Polypropylenes