Parts | Days | Selection | Search | Downloads | Help

DY: Dynamik und Statistische Physik

DY 16: Growth Processes and Surface Properties

DY 16.1: Talk

Monday, March 27, 2006, 16:15–16:30, H\"UL 186

Crack Propagation as a Free Boundary Problem — •Denis Pilipenko, Robert Spatschek, Efim Brener, and Heiner Mueller-Krumbhaar — Institut fuer Festkoerperforschung, Forschungszentrum 52425 Juelich

We demonstrate a macroscopic theory of fracture in the spirit of nonequilibrium growth processes in pattern formation. The theory is based only on the dynamical theory of elasticity, surface energy and elastically induced phase transitions between a hard and a soft solid phase. Alternatively, crack growth can be described by surface diffusion along the crack. Although it is commonly believed that crack growth is dictated by the microscopic details in the vicinity of the tip, and despite the simplicity of our continuum theory, it predicts many important features of fracture. Among them is the limitation of the steady state growth velocity to values appreciably below the Rayleigh speed (the speed of sound) and tip blunting. We present a multipole expansion technique to solve numerically the problem of steady state growth in a very efficient way, using a sharp interface description of the propagating crack front. The results are discussed and compared to phase field simulations.