<> "The repository administrator has not yet configured an RDF license."^^ . <> . . . "A nonlocal cohesive zone model for studying crack propagation in mechanical systems with finite thickness interfaces"^^ . "Finite thickness regions between heterogeneous material constituents are often simplified as zerothickness\r\ninterfaces. Then, the cohesive zone model (CZM) is employed, establishing a constitutive relation between tractions and displacement discontinuities. The shape of the CZM is usually chosen as simple as possible for numerical reasons, rather than being physically meaningful. Therefore, the reliability and the predictive capabilities of these models are a serious concern. In this contribution, the complex nonlinear damage phenomena occurring in finite thickness interface regions are modeled using damage mechanics. The derived nonlinear relation between cohesive\r\ntractions and anelastic displacements is then reinterpreted as a new nonlocal CZM. Depending on\r\nthe ductility of the material, different shapes of the CZM can be recovered, from linear and bilinear\r\nsoftening curves, typical of brittle materials, to bell-shaped curves typical of ductile materials. It is\r\nalso shown that the parameters of the damage law can be tuned according to molecular dynamics simulations.\r\nThe implementation of the proposed nonlocal CZM in the finite element method is then presented. Special attention is given to the numerical treatment of the related nonlocality and to the computation of the tangent stiffness matrix to be used in the Newton-Raphson method for the solution of the nonlinear boundary value problem.\r\nThe numerical model is applied to polycrystalline materials and it is shown that the nonlocal CZM is able to reproduce realistic statistical distributions of Mode I fracture energies, as a consequence of the interface thickness distribution. Finally, we demonstrate that the relation between interface thickness and grain size can also be used to explain the grain size effects on the material\r\ntensile strength, namely the Hall-Petch law and its inversion at the nanoscale."^^ . "2011" . . "Publi&Stampa Edizioni"^^ . . "Publi&Stampa Edizioni"^^ . . . . . . . . . . . "Marco"^^ . "Paggi"^^ . "Marco Paggi"^^ . . "Peter"^^ . "Wriggers"^^ . "Peter Wriggers"^^ . . . . . "HTML Summary of #2071 \n\nA nonlocal cohesive zone model for studying crack propagation in mechanical systems with finite thickness interfaces\n\n" . "text/html" . . . "TJ Mechanical engineering and machinery"@en . .