Ripplocations: A universal deformation mechanism in layered solids

Abstract

Layered materials and formations are ubiquitous in Nature and span the gamut from individual graphene layers in graphite, to layered composites, to geologic formations. And while the similarities in the deformation of the latter two have been recognized, that the same physics applies at the atomic scale has not. Using atomistic simulations on graphite, and simple instrumented cylindrical indentation experiments on decks of cards and thin steel sheets the authors show that, in all cases, confined buckling leads to the nucleation of multiple ripplocations that rapidly propagate away from under the indenter in a wavelike manner. Upon unloading, they disappear, after dissipating considerable frictional energy. In short, Nature's solution for the deformation of all layered solids, g20 orders of magnitude in scale, is as simple as it is universal: buckling. To be able to shed light on how an earthquake propagates from studying the deformation of graphite and vice versa is quite astonishing and remarkable indeed.