https://hal-polytechnique.archives-ouvertes.fr/hal-01219714Mbiakop, A.A.MbiakopConstantinescu, A.A.ConstantinescuLMS - Laboratoire de mécanique des solides - X - École polytechnique - Mines Paris - PSL (École nationale supérieure des mines de Paris) - PSL - Université Paris sciences et lettres - CNRS - Centre National de la Recherche ScientifiqueDanas, KostasKostasDanasLMS - Laboratoire de mécanique des solides - X - École polytechnique - Mines Paris - PSL (École nationale supérieure des mines de Paris) - PSL - Université Paris sciences et lettres - CNRS - Centre National de la Recherche ScientifiqueOn void shape effects of periodic elasto-plastic materials subjected to cyclic loadingHAL CCSD2015[PHYS.MECA.MSMECA] Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph]Constantinescu, Andrei2020-02-24 19:16:222022-10-22 04:54:492020-02-26 11:30:05enJournal articleshttps://hal-polytechnique.archives-ouvertes.fr/hal-01219714/document10.1016/j.euromechsol.2014.09.001application/pdf1AbstractThis work investigates the effect of cyclic loading upon periodic elasto-plastic porous materials. The aim is to understand the evolution of the underlying microstructure, described here with a single void embedded in a cubic unit-cell. Periodic finite element (FEM) calculations are carried out under a finite strain deformation process keeping the absolute value of the stress triaxiality and the Lode angle constant during the cycle. As a result of the applied loading conditions, the void geometry, both volume and shape, change significantly leading to porosity and void shape ratcheting. The void shape becomes non-spherical from the very first cycle leading to a markedly asymmetric cyclic response of the material. This, in turn, results in an observed maximum stress as a function of the number of cycles. In addition, even though the average applied strains are relatively small, the local strains near the void surface increase significantly inducing a significant localization of the deformation. Finally, several initial void shape configurations are also considered. In the majority of the cases studied, the void evolves into a crack-type shape in the direction of the minimum absolute stress. This, in turn, is consistent with a configuration corresponding to a crack subjected to a mode I cyclic loading.