MESOSCALE MODELING OFPOLYMER FOAMS
Résumé
The primary objective of this study is to gain a better understanding of the correlation between the microstructures of foamed polymers and their mechanical properties. X-Ray tomography was used to analyze polypropylene foam specimens obtained from injected plaques with varying thicknesses and microstructure morphologies. The resulting tomography scans were digitalized and meshed for numerical simulations on representative volume elements (RVEs) using the parallel C++ library Cimlib developed at CEMEF. The numerical methods described in this study focused on generating exact and statistical RVEs using immerged or body-fitted strategies in the context of finite element analysis, level set framework, and meshing adaptation [1,2].
The numerical results conducted for both real and statistical RVEs were compared to experimental testing performed under tension and compression at different strain rates using digital image correlation. The simulations performed at the mesoscale were found to agree well with the experimental tests conducted at the macroscale. Design of experiment was also used for optimizing foam microstructure and getting relevant mechanical properties.
[1] H. Digonnet, L. Silva, et T. Coupez, in AIP Conference Proceedings, Porto (Portugal), vol. 908, p. 269‑274, 23 (2007)
[2] M. Shakoor, M. Bernacki, et P.-O. Bouchard, Eng. Fract. Mech., vol. 147, p. 398‑417 (2015)