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Path (un)predictability of two interacting cracks in polycarbonate sheets using Digital Image Correlation.

ABSTRACT: Crack propagation is tracked here with Digital Image Correlation analysis in the test case of two cracks propagating in opposite directions in polycarbonate, a material with high ductility and a large Fracture Process Zone (FPZ). Depending on the initial distances between the two crack tips, one may observe different complex crack paths with in particular a regime where the two cracks repel each other prior to being attracted. We show by strain field analysis how this can be understood according to the principle of local symmetry: the propagation is to the direction where the local shear - mode KII in fracture mechanics language - is zero. Thus the interactions exhibited by the cracks arise from symmetry, from the initial geometry, and from the material properties which induce the FPZ. This complexity makes any long-range prediction of the path(s) impossible.

SUBMITTER: Koivisto J

PROVIDER: S-EPMC5006083 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Path (un)predictability of two interacting cracks in polycarbonate sheets using Digital Image Correlation.

Koivisto J J Dalbe M-J MJ Alava M J MJ Santucci S S

Scientific reports 20160831

Crack propagation is tracked here with Digital Image Correlation analysis in the test case of two cracks propagating in opposite directions in polycarbonate, a material with high ductility and a large Fracture Process Zone (FPZ). Depending on the initial distances between the two crack tips, one may observe different complex crack paths with in particular a regime where the two cracks repel each other prior to being attracted. We show by strain field analysis how this can be understood according ...[more]

PMID: 27578388

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