Analysis of unbalanced laminate composites with imperfect interphase: Effective properties via asymptotic homogenization method

This work addresses the Asymptotic Homogenization Method (AHM) to find all the non-zero independent constants of the fourth-order elasticity tensor of a theoretically infinite periodically laminated composite. The concept of Unit Cell describes the domain, comprised of two orthotropic composite plies separated by an isotropic interphase. A general case with an unbalanced composite is considered. Thus, the coupled components of the tensor are expected. Both analytical and numerical solutions are derived. In addition, an interphase degradation model is proposed to evaluate its effect on the effective properties of the media. Two different stacking sequences are considered with five degrees of interphase imperfection each. The results show good agreement between the analytical and numerical solutions. In addition, it is clear that the more imperfect the interphase is, the more affected the effective properties of the media are, especially those dependent on the stacking direction.

Asymptotic homogenization of metamaterials elastic plates

The asymptotic homogenization technique is applied to evaluate the effective properties of thin plates with periodic heterogeneity. The effect of shear deformation in the homogenization process is evidenced and the role of cell slenderness, besides that of the plate, is clarified by several numerical analyses.

MODELING OF MECHANICAL BEHAVIOUR OF A 1D, LINEAR AND MICROPERIODIC COMPOSITE, WITH FAILURE, VIA THE ASYMPTOTIC HOMOGENIZATION METHOD

In this paper the Asymptotic Homogenization Method is combinedwith a model of Hyperelasticity with softening (wich models the mechanical failureof the material), with the purpose of estimating the mechanical behaviour ofmicroperiodic composites in the way to reproduces better the behaviour obtainedin experiments, found in the literature. This hybrid approach brings somesatisfactory results, showing that the (hypothetical)composite studied presentseffective behaviour very close to the expected from the Hyperelasticity model. Thatis a very important fact because can be used as a tool to predict the failure ofcomposite materials, trough its constituent materials informations. This evaluatingneeds more steps, to be possible much bigger and strong conclusions, however theresults obtained until now seems like very promissory.