Plastic instabilities and their relation to fracture

When plastic instabilities occur the plastic deformation ahead of a crack tip is heterogeneous. This heterogeneity changes the rate of plastic dissipation ahead of a crack. Thus, depending on the nature of the instability (steady as persistant slip bands, propagative as Portevin-Le Châtelier bands) the toughness K is influenced by plastic instabilities. In parallel, plastic localization is known to produce enhanced damage, very localized, …