Published in Computational Materials Science
This paper discusses covariance and material objectivity in continuum mechanics. The aim is to extend the mathematical framework of constitutive relations to the four-dimensional (4D) formalism of the General Relativity theory. First, it is demonstrated that 4D general linear or non-linear, isotropic or anisotropic relations can be obtained, no mat...
Published in Computational Materials Science
A first-principles approach is used to study the structural and dynamical stability of the hypothetical RbN and CsN compounds. First, I review briefly our earlier work on the origin of half-metallicity and then I present detailed results on the mechanical and dynamical properties obtained from the ultra soft pseudopotential approach. The elastic co...
Published in Computational Materials Science
An original phase-field model dedicated to the calculation of dislocation sink strength is presented. Through a three-step validation procedure, it is shown to predict with an excellent accuracy the value of the sink strength with or without elasticity in numerous test cases for which an analytical solution is known. Further analysis shows that exi...
Published in Computational Materials Science
In many exposure environments, capillary absorption of water controls the rate of deterioration of concrete. This paper presents a three-dimensional numerical investigation of capillary absorption by treating concrete as a heterogeneous composite discretised into a cubic lattice. The lattice elements were considered as conductive “pipes” with trans...
Published in Computational Materials Science
The relevance of three numerical thermo-mechanical models of materials behavior is investigated to assess stresses magnitudes stored in three layers polyethylene coating during the quenching step of a coated steel pipe. Computations results stemming from thermo-elastic, thermo-plastic and thermo-viscoelastic models are compared. Benefits of thermo-...
Published in Computational Materials Science
The present paper deals with the identification of the parameters of a generalized GTN model and the characterization of ductile damage for a high carbon steel by both X-ray micro-tomography and “macroscopic” mechanical tests. First, in situ X-ray micro-tomography tensile tests are performed and the results are used for the modeling of ductile dama...
Published in Computational Materials Science
The asymptotic discrete expansion method is used to construct the initial yield surface of periodic 2D trusses of beams and the evolution of the yield surface with ongoing hardening. It allows simulating the elastoplastic homogenized response of such lattices subjected to multiaxial loadings. The proposed methodology is quite general, as the repres...
Published in Computational Materials Science
The magnetic properties and electronic structures and of GdBi are reviewed in this manuscript. Self-consistent ab initio calculations, based on DFT (Density Functional Theory) approach and using FLAPW (Full potential Linear Augmented Plane Wave) method within GGA+U approximation, are performed to investigate both electronic and magnetic properties ...
Published in Computational Materials Science
The aim of this study is to present an original approach for the simulation of sintering with Discrete Element Method, using a Non Smooth Method called Contact Dynamics.Recently, there have been numerous papers about the simulation of sintering using Discrete Element approaches. Most of these papers use Smooth Dynamics and their results match well ...
Published in Computational Materials Science
Computational continuum model for predicting the effect of interphase on the large deformation behaviour of polymer–clay nanocomposites during semi-solid state processing was proposed in this work. The interphase was assumed to exist and modelled here as a layer of finite thickness, which resided perfectly bonded atop of each surface of individual ...
