Frequency and time viscoelectroelastic effective properties modeling of heterogeneous and multi-coated piezoelectric composite materials

2014 ◽  
Vol 113 ◽  
pp. 281-297 ◽  
Author(s):  
L. Azrar ◽  
A. Bakkali ◽  
A.A. Aljinaidi
Keyword(s):  
Composite Materials ◽  
Effective Properties ◽  
Piezoelectric Composite

An analysis of piezoelectric composite materials containing ellipsoidal inhomogeneities

1993 ◽  
Vol 443 (1918) ◽  
pp. 265-287 ◽  
Keyword(s):  
Composite Materials ◽  
Effective Properties ◽  
Mean Field ◽  
Piezoelectric Medium ◽  
Piezoelectric Composite ◽  
High Concentration ◽  
Reinforced Composite ◽  
The Matrix ◽  
Eshelby’S Tensor ◽  
Piezoelectric Solids

A set of four tensors corresponding to Eshelby’s tensor in elasticity are obtained for an ellipsoidal inclusion embedded in an infinite piezoelectric medium. These tensors, which describe the elastic, piezoelectric, and dielectric constraint of the matrix, are obtained from W. F. Deeg’s solution to inclusion and inhomogeneity problems in piezoelectric solids. These tensors are then used as the backbone in the development of a micromechanics theory to predict the effective elastic, dielectric, and piezoelectric moduli of particle and fibre reinforced composite materials. The effects of interaction among inhomogeneities at finite concentrations are approximated through the Mori-Tanaka mean field approach. This approach, although widely utilized in the study of uncoupled elastic and dielectric behaviour, has not before been applied to the study of coupled behaviour. To help ensure confidence in the theory, the analytical predictions are proven to be self-consistent, diagonally symmetric, and to exhibit the correct behaviour in the low and high concentration limits. Finally, numerical results are presented to illustrate the effects of the concentration, shape, and material properties of the reinforcement on the effective properties of piezoelectric composites and analytical predictions are shown to result in good agreement with existing experimental data.

Consistent Hashin-Shtrikman Bounds on the Effective Properties of Periodic Composite Materials

1999 ◽  
Vol 66 (4) ◽  
pp. 858-866
Author(s):  
P. Bisegna ◽  
R. Luciano
Keyword(s):  
Composite Materials ◽  
Saddle Point ◽  
Variational Principles ◽  
Effective Properties ◽  
The Other ◽  
Constitutive Behavior ◽  
Homogenization Problem ◽  
Numerical Examples ◽  
Periodic Composites ◽  
Periodic Composite

In this paper the four classical Hashin-Shtrikman variational principles, applied to the homogenization problem for periodic composites with a nonlinear hyperelastic constitutive behavior, are analyzed. It is proved that two of them are indeed minimum principles while the other two are saddle point principles. As a consequence, every approximation of the former ones provide bounds on the effective properties of composite bodies, while approximations of the latter ones may supply inconsistent bounds, as it is shown by two numerical examples. Nevertheless, the approximations of the saddle point principles are expected to provide better estimates than the approximations of the minimum principles.

Active-Passive Damping Characteristics of Extension and Shear Mode Piezoelectric Fiber Nano-Reinforced Composite (PFNRC)

2017 ◽  
Author(s):  
Kepin Kavathia ◽  
Manoj Settipalli ◽  
Samikkannu Raja
Keyword(s):  
Carbon Nanotubes ◽  
Epoxy Matrix ◽  
Effective Properties ◽  
Past Research ◽  
Piezoelectric Composite ◽  
Passive Damping ◽  
The Past ◽  
Reinforced Composite ◽  
Walled Carbon Nanotubes ◽  
Piezoelectric Fiber

This paper presents a simulation-based study to investigate the damping properties of a novel piezocomposite, consisting of piezoelectric fiber and epoxy reinforced with randomly orientated double walled carbon nanotubes (DWCNT), termed as piezoelectric fiber nano reinforced composite (PFNRC). Authors have observed that the past research dealt with the effect of aligned single walled carbon nanotubes (CNT) on active damping of piezoelectric composite in extension mode (e13 and e33). It is known from the past research that DWCNT inclusions improve the passive damping of a composite. Therefore, the authors use DWCNT inclusions to study the active-passive damping of the piezoelectric composite, in this article. The random orientation of the DWCNT is considered to replicate the physical composite as it known that aligning CNTs in a single direction is not feasible due to fabrication constraints. A multistep homogenization method involving Method of Cells (MOC) is employed to obtain effective properties of PFNRC. A modified 3D-MOC is used to obtain the effective properties of epoxy matrix with DWCNT inclusions (DWCNT-epoxy), considering the effect of nano particle agglomeration. A 2D-MOC is then implemented with long fiber PZT as the active material and DWCNT-epoxy as the matrix. This procedure is followed for computing the effective material properties of extension (e33) as well as shear (e15) mode of PFNRC, when DWCNT inclusions are added into the epoxy matrix at different weight percentages. The constitutive equations are derived with the help of Maple and simulated in MATLAB. These results are used to compare the active-passive damping performance of the composites using a single degree of freedom damping model, employing Newmark’s numerical integration method. The active damping performance of the composites is evaluated by varying the displacement and velocity gains in a negative feedback system. The main focus of the study is to find the most efficient operating mode of the proposed composite for damping of structural vibrations.

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