Electromechanical response of 1–3 piezoelectric composites: Effect of fiber shape

Abstract

An analytical model and a finite element based numerical model is presented to study the effects of fiber shape on the complete elastic, dielectric, and piezoelectric properties of a general 1–3 long-fiber “longitudinal” and “transverse” composite with elastically anisotropic and piezoelectrically active constituents. Six classes of piezoelectric composites, each with several prismatic and nonprismatic shaped fibers, in two widely different ceramic and polymer matrices are considered. It is demonstrated that (i) while the longitudinal material properties are insensitive to changes in the shape of the fiber phase, the transverse properties display a strong dependence on the shape of the fiber phase, particularly for the polymer-matrix composites; (ii) while the figures of merit such as the longitudinal piezoelectric coupling constant and the acoustic impedance do not demonstrate significant fiber shape effects, the transverse sensing ability of the polymer-matrix transverse composite is significantly influenced by the fiber shape with the composites with prolate shaped fibers providing the highest piezoelectric voltage constant.

Improving the d33 and g33 properties of 0-3 piezoelectric composites by dielectrophoresis

“…An alternative is the 1-3 type composite, in which continuous aligned fibers or precisely shaped pillars of piezoelectric material inside the matrix are employed. 12,13 However, such systems typically involve intricate processing methods, often involving dicing a sintered block of ceramic or complex shaping of the delicate green ceramic mixture. 14 The dielectrophoretic effect can be utilized to manipulate particles dispersed in a fluid medium [15][16][17][18] and offers a simple alternative approach to create oriented particle filled polymer composites with anisotropic properties.…”

Anisotropic piezoelectric properties of 1–3 ceramic / polymer composites comprising rods with elliptic cross section

“…A transition from a transversely isotropic composite to an anisotropic one was considered in paper [11] where 36 classes of the piezo-active 1-3 composites were introduced. Very recently, the effect of the rod shape on the effective electromechanical properties was studied for the 1-3 "longitudinal" and "transverse" composites with elastically anisotropic and piezoelectrically active components [14]. However, the anisotropic piezo-active composites comprising rods with elliptic cross section were not yet considered in detail, especially for different combinations of the FC and polymer components.…”

“…The prediction of the effective electromechanical properties in our work is also carried out using the FEM. It should be mentioned that in the last decades, the FEM has been applied to 1-3 FC / polymer composites with a periodic arrangement of the rods (see, e.g., papers [10,12,[14][15][16]). Following the FEM, the unit-cell model of the 1-3 composite with the regular arrangement of the rods ( Fig.…”

“…The upper limit m=π / 4 corresponds to the ratio of the area of the ellipse to the area of the rectangle on condition that this ellipse has been inscribed into the rectangle. This rectangle is regarded as a base of a representative unit cell [10,[14][15][16] of the 1-3 composite. The prediction of the effective electromechanical properties in our work is also carried out using the FEM.…”

“…As a consequence, the effective parameters of the 1-3 FC / polymer composite considerably depend [2][3][4][5]7] on microgeometric features, electromechanical properties and volume fractions of the components, poling conditions, etc. The effective electromechanical properties were predicted and analysed for the 1-3 composites with the FC rods having the following cross section: circle [2,[8][9][10][11][12], square [7,[13][14][15][16], rectangle [17], ellipse [14,18], octagon [14], and cross [14]. Among FC components in the 1-3 composites one can mention compositions based on Pb(Zr, Ti)O 3 (PZT-type) [2-5, 7-11, 14-16] or Pb(Ca, Ti)O 3 [7,12,15].…”