Universal aspects of dynamic fracture in brittle materials

Ariel Livne*, Jay Fineberg

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

We present an experimental study of the dynamics of rapid fracture in brittle amorphous materials. In this study we utilize a class of model materials, polyacrylamide gels, in which the relevant sound speeds can be reduced by 2-3 orders of magnitude compared to "standard" brittle materials. We first demonstrate that dynamic fracture in polyacrylamide gels has characteristic features which are identical to those observed in well-studied brittle materials, such as brittle plastics and glasses. These features include the existence of a critical velocity beyond which frustrated crack branching occurs (Fineberg [1], Sharon [2]) and the profile of the micro-branches formed. We then examine the behavior of the crack fronts, which are the 1D fronts defined by the leading edge of a propagating crack. During fracture, a crack front can be locally perturbed by either an externally introduced inclusion or, dynamically, by the generation of a micro-branch. Comparison of the behavior of the excited fronts in both gels and in soda-lime glass reveals that, once again, many aspects of the dynamics of these excited fronts are the same in both materials. These include both the generation of coherent, localized waves ([Morrissey [3], Ramanathan [4], Sagy [5], Sharon [6]) ("front waves") which propagate along the crack front as well as the appearance of crack front inertia. Crack front inertia is embodied by a "memory" effect of the crack front in which directed roughly periodic lines of spatially localized micro-branches are generated. These lines are aligned in the direction of propagation (Fineberg [7], Sharon [8]) and the spacing between successive microbranches is proportional to their width (in the direction normal to the propagation direction). This scaling is identical in both glass and gels.

Original languageEnglish
Title of host publication11th International Conference on Fracture 2005, ICF11
Pages3552-3557
Number of pages6
StatePublished - 2005
Event11th International Conference on Fracture 2005, ICF11 - Turin, Italy
Duration: 20 Mar 200525 Mar 2005

Publication series

Name11th International Conference on Fracture 2005, ICF11
Volume5

Conference

Conference11th International Conference on Fracture 2005, ICF11
Country/TerritoryItaly
CityTurin
Period20/03/0525/03/05

Fingerprint

Dive into the research topics of 'Universal aspects of dynamic fracture in brittle materials'. Together they form a unique fingerprint.

Cite this