Acoustic emissions from rapidly moving cracks

Abstract
Linear elasticity is unable to predict completely the dynamics of a rapidly moving crack without the addition of a phenomenological fracture energy. Our measurements of acoustic emission, crack velocity, and surface structure demonstrate quantitatively similar dynamical fracture behavior in two very different materials, polymethylmethacrylate and soda-lime glass. This unexpected agreement suggests that there exist universal features of the fracture energy that result from dissipation of energy in a dynamical instability.