Micromechanical approach for the behaviour of open cell foams
Keywords:
open cell, micromechanics, foams, elasticity, viscoelasticityAbstract
The objective of this paper is the prediction of the macroscopic behaviour of open-cell foams in elasticity and viscoelasticity as function of their microstructure by using a micromechanical approach. Open cellular materials are characterised by remarkable mechanical properties with light weight. Such materials are largely used in various applications mainly in energy absorption. Polyurethane foam is used as an application once its microstructure is majorly described by an open-cell foam. Finite Element computations are performed on a unit cell subjected to periodic boundary conditions. Then, a micromechanical model based on Cosserat homogenisation framework is performed to predict the macroscopic elasticity. The linear viscoelastic behaviour is deduced from elastic results by taking advantage of correspondence principle. Finally, the results are confronted to various models developed in literature.
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