Browsing NTNU Open by Author "Benallal, Ahmed"
Now showing items 1-9 of 9
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A study of the influence of precipitate free zones on the strain localization and failure of the aluminium alloy AA7075-T651
Fourmeau, Marion; Marioara, Calin Daniel; Børvik, Tore; Benallal, Ahmed; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2015)Age-hardened aluminium alloys have various degrees of precipitate-free zones (PFZs) along grain boundaries (GBs). The PFZs are weak zones and their existence promotes combined transgranular and intergranular fracture, thus ... -
A thermo-elasto-viscoplastic constitutive model for polymers
Johnsen, Joakim; Clausen, Arild Holm; Grytten, Frode; Benallal, Ahmed; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2018)In this study, a thermo-elasto-viscoplastic model is developed for a low density cross-linked polyethylene (XLPE) in an attempt to describe the combined effects of temperature and strain rate on the stress-strain response ... -
Anisotropic tensile failure of metals by the strain localization theory: An application to a high-strength aluminium alloy
Morin, David; Fourmeau, Marion; Børvik, Tore; Benallal, Ahmed; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2018)This paper investigates the influence of plastic anisotropy on the tensile ductility of a high-strength aluminium alloy. To this end, finite element simulations of smooth and notched tension tests in different material ... -
Effective behaviour of porous ductile solids with a non-quadratic isotropic matrix yield surface
Dæhli, Lars Edvard Blystad; Hopperstad, Odd Sture; Benallal, Ahmed (Journal article; Peer reviewed, 2019)In this study, we examine the macroscopic yielding of isotropic porous ductile solids having a matrix yield function dependent on the second and third deviatoric stress invariants. Numerical limit analyses using a ... -
Experimental and numerical study on the behaviour of PVC and HDPE in biaxial tension
Ognedal, Anne Serine; Clausen, Arild Holm; Polanco-Loria, Mario A.; Benallal, Ahmed; raka, bumedijen; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2012)This paper presents and discusses a set of biaxial tests on two different polymer materials; PVC and HDPE. The biaxial tests are used to evaluate a hyperelastic–viscoplastic constitutive model involving the pressure-dependent ... -
Numerical study of ductile failure under non-proportional loading
Morin, David; Dæhli, Lars Edvard; Børvik, Tore; Benallal, Ahmed; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2019)This paper investigates two numerical methods for predicting the initiation of ductile failure under moderately and strongly non-proportional loading paths. Two distinct phenomena are considered as indicators for the ... -
A Numerical Study on Ductile Failure of Porous Ductile Solids With Rate-Dependent Matrix Behavior
Dæhli, Lars Edvard Blystad; Morin, David; Børvik, Tore; Benallal, Ahmed; Hopperstad, Odd Sture (Peer reviewed; Journal article, 2020)This work examines the effects of loading rate on the plastic flow and ductile failure of porous solids exhibiting rate-dependent behavior relevant to many structural metals. Two different modeling approaches for ductile ... -
On crystallographic aspects of heterogeneous plastic flow during ductile tearing: 3D measurements and crystal plasticity simulations for AA7075-T651
Morgeneyer, Thilo; Khadyko, Mikhail; Buljac, A; Helfen, Lukas; Hild, Francois; Benallal, Ahmed; Børvik, Tore; Hopperstad, Odd Sture (Peer reviewed; Journal article, 2021)Crystallographic aspects of heterogeneous plastic flow during ductile tearing are assessed experimentally by combining in situ synchrotron laminography imaging of notched flat samples with a full-field measurement technique ... -
On the description of ductile fracture in metals by the strain localization theory
Morin, David; Hopperstad, Odd Sture; Benallal, Ahmed (Journal article; Peer reviewed, 2017)Numerical simulations based on the bifurcation and imperfection versions of the strain localization theory are used in this paper to predict the failure loci of metals and applied to an advanced high strength steel subjected ...