title: How cracks are hot and cool: a burning issue for paper.
abstract: Material failure is accompanied by important heat exchange, with extremely high temperature - thousands of degrees - reached at crack tips. Such a temperature may subsequently alter the mechanical properties of stressed solids, and finally facilitate their rupture. Thermal runaway weakening processes could indeed explain stick-slip motions and even be responsible for deep earthquakes. Therefore, to better understand catastrophic rupture events, it appears crucial to establish an accurate energy budget of fracture propagation from a clear measure of various energy dissipation sources. In this work, combining analytical calculations and numerical simulations, we directly relate the temperature field around a moving crack tip to the part α of mechanical energy converted into heat. By monitoring the slow crack growth in paper sheets using an infrared camera, we measure a significant fraction α = 12% ± 4%. Besides, we show that (self-generated) heat accumulation could weaken our samples by microfiber combustion, and lead to a fast crack/dynamic failure/regime.
authors.affiliation: Institut de Physique du Globe de Strasbourg, CNRS, EOST-University of Strasbourg, 5 rue Descartes, 67084 Strasbourg Cedex, France. renaud.toussaint@unistra.fr.
authors.forename: Renaud
authors.initials: R
authors.lastname: Toussaint
authors.forename: Olivier
authors.initials: O
authors.lastname: Lengliné
authors.forename: Stéphane
authors.initials: S
authors.lastname: Santucci
authors.forename: Tom
authors.initials: T
authors.lastname: Vincent-Dospital
authors.forename: Muriel
authors.initials: M
authors.lastname: Naert-Guillot
authors.forename: Knut Jørgen
authors.initials: KJ
authors.lastname: Måløy