(Dr. Yves Berthelot, advisor)
"Frequency Dependent Micromechanical Model of Viscoelastic Material with Coated Inclusion"
This study is concerned with modeling the elastic moduli of elastomers filled with coated micro-inclusions. A study of existing effective medium theories (EMT) for macroscopically homogeneous viscoelastic composites is presented. This is then followed by a discussion of the assumptions and subsequent limitations of these models. In particular, the static models of Kerner and the self-consistent micromechanical approach of Cherkaoui are evaluated and compared with experimental data given in the literature. Material frequency response and the quasi-static modeling approach are then investigated. The Gaunaurd and Überall (GU) approach as applied by Baird, Kerr, and Townend (BKT) is explored, evaluated, and compared with experimental values from the literature. Finally, the self-consistent micromechanical model is extended to include the frequency dependence of the material and the results are compared with experimental values. Justification of the use of this model in the frequency regime is given and the advantages of this approach over the BKT approach are discussed. Suggestions for further investigation and verification through Finite Element modeling are then discussed.