We are working on the mechanical behavior of foams submitted to severe compression. The internship is about runing Abaqus simulations and analyzing the microstructure pre and post loading to better understand the link between the microstructure and the macroscopic behavior.If interested please contact me at julie . diani [ ] polytechnique.edu
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Nonlinear behavior of a soft matrix highly filled with randomly spherical particle or voids
When highly reinforced a soft matrix, like an elastomer matrix, undergoes incredibly localized high strain where particles nearly touch. Therefore, it requires extensive remeshing efforts in an order to estimate numerically the equivalent homogeneous behavior of such a composite. We did that, using Abaqus *MAP SOLUTION option. This allowed to provide original numerical stress-strain responses […]
Is it possible to characterize the linear viscoelasticity of an anisotropic carbon fibers reinforced thermoplastic polymer?
When dealing with isotropic polymer, it is easy to characterize the linear viscoelasticity in the lab via dynamic mechanic analysis in tension, torsion. What about for a transversely isotropic material such as a carbon fibers reinforced polymer? Actually, one may find out that it is not possible to directly assert any of the five parameters […]
A finite strain viscoelastic model with damage and tension/compression asymmetry
In an effort to bring some clarification on the vast literature on finite strain viscoelastic models, initially defined for elastomers, a review of the pioneering models on finite strain viscoelastic from Le Tallec et al. (1993), Lion (1997) and Reese and Govindjee (1998) has shown that these models are totally equivalent [1]. It is not […]
Comparison between two fracture tests, SENB vs. DCDC applied to acrylate polymers
We have compared the mode I opening critical energy release rate (GIc) measured using the single edge notch bending test and double cleavage drilled compression test on an elastic fragile PMMA and a bulk viscoplastic acrylate used as a glue for wind turbine blades. The study details the experimental procedure, for the crack initiation and […]
Damage phase-field approach vs. Cohesive zone model for double cleavage drilled compression fracture test
The double cleavage drilled compression (DCDC) test has been introduced for glass but also extended to test polymer. It is a slender prismatic specimen with a hole in its middle and cracks that are initiated at both poles. It is interesting because the loading is uniaxial compression and the cracks are submitted to opening mode […]
Damping optimization of polymer structures
Polymers are viscoelastic and therefore are interesting for damping applications, especially when used at temperatures laying in their glassy-to-rubbery transition where the material is showing significant viscoelasticity. During his PhD co-advised by Gregoire Allaire, Samuel Amstutz and me, Antoni Joubert has worked on the shape optimization of thin structures such as beams and plates to […]
Creep behavior of soft adhesives
Single-lap joint creep behaviour of two soft adhesives We have submitted two hot melt pressure sensitive adhesives (HMPSA) to bonded joint creep tests. While glassy state adhesives such as epoxys are often studied in the literature, data on soft adhesives that are in the rubbery state are scarce. These adhesives have applications such as sealing […]
Impact of the microstructure on the mechanical behavior of PEBAX foams
Five PEBAX foams provided by Arkema and obtained by mold-opening foam injection process has been studied. One one side, the microstructures have been characterized by DSC for the chemical and physical properties, and by scanning electron microscope image analysis for the structural properties. On the other side, the linear elasticity as well as the non-linear […]
Python FFT homogenization routine for linear viscoelasticity
This is the python routine I used to calculate the linear viscoelasticity (storage and loss shear moduli) of worm-like microstructures define in the paper on linear viscoelasticity of IPNs. This routine may be used for any two-phase materials with the microstructure of your choice.You need two input.txt (phase1.txt and phase2.txt) files for the behavior constitutive […]