De-localizing brittle fracture

Oguz Umut Salman (1) , L Truskinovsky (2)

1 LSPM - Laboratoire des Sciences des Procédés et des Matériaux
2 PMMH - Physique et mécanique des milieux hétérogenes (UMR 7636)

Localization of damage in conventional brittle materials is the source of a host of undesirable effects. In this paper, we show how artificially engineered metamaterials with all brittle constituents can be designed to ensure that every breakable sub-element fails independently. The crucial role in the proposed design is played by high contrast composite sub-structures with zero-stiffness, furnishing nonlocal stress redistribution. The de-localized cracking of the resulting nominally brittle systems can be linked to the fact that their continuum description is dominated by gradient rather than classical elasticity. By engineering a crossover from brittle to effectively ductile (quasi-brittle) behavior, we elucidate the structural aspects distinguishing macro-cracking-dominated fracture from micro-cracking-dominated damage.

Mots clés: Metamaterials; quasi-brittleness; ductility; micro-cracking; damage; fracture; high gradients; phase-field

Domaines: Sciences de l'ingénieur [physics]; Mécanique des matériaux [physics.class-ph]; Formation de Structures et Solitons [nlin.PS]; Physique [physics]; Mécanique [physics]

Oguz Umut Salman, L Truskinovsky. De-localizing brittle fracture. 2020. ⟨hal-02993994⟩