Micromechanical Modeling of Particulate Composites for Damping of Acoustic Waves

The self-consistent (SC) micromechanical model of a composite containing coated micro-inclusions, originally proposed in the static regime by Cherkaoui et al. (1994, J. Eng. Mater. Technol., 116, 274–278), is implemented in the quasistatic regime by the introduction of frequency dependent complex moduli for the matrix material. The original model is improved by using dilute strain concentration tensor (DSCT) formulation. It is shown that these concentration tensors can be used to approximate effective composite behavior of composites containing ellipsoidal inclusions having a known orientation distribution or of composites containing multiple types of coated inclusions. The DSCT formulation is also shown to be capable of modeling the effects of multiple scales (submicron-meso-macro), as well as that of a distribution of inclusion coating thicknesses. Various potential material modeling applications are verified through comparison with experimental data in the literature. Notably, the DSCT SC model is applied in the quasistatic regime for calculation of acoustic transmission loss of a slab of viscoelastic composite submerged in water for the range of frequencies between $0-100kHz$ and compared with experimental data of Baird et al. (1999, J. Acoust. Soc. Am., 105, 1527–1538).