IGM Colloquium: The shape of torn sheets: fracture, geometry and anisotropy

Our everyday experience of tearing (fracture in thin sheets) can be frustrating (not-so-"easy opening" packages, removing adhesive tape…).
In fact tearing paths are very reproducible and we will show that they obey simple laws, with consequences in engineering at many scales, including in many examples around us.

In this seminar, I will review several tearing problems, where experimental fracture path are very robust. I will show how a simplistic (geometric) framework, based on energy arguments, provides very insightful information. However, a complete description should include additional effects, and in particular anisotropy, a consequence of the manufacturing of thin sheets; tearing a piece a paper brings us to deep questions in fracture mechanics.

Bio:
B. Roman is a senior CNRS scientist in Paris (PMMH,ESPCI), working on then non-linear mechanics of slender bodies (tearing, crumpling, wrinkling, capillary folding, morphing..).
PhD in physics in Marseille, Postdoc in Texas, and in Chile, joined CNRS in Paris at ESPCI and teached mechanics in Ecole Polytechnique (Paris).