Pyroelectric and pyromagnetic coefficients of functionally graded multilayered multiferroic composites

Abstract

This paper presents a method for analyzing some product properties of functionally graded magnetoelectro-thermoelastic (METE) multilayer composites. The method is based on an exact matrix formulation for the effective properties of multilayer composites with various coupled physical effects including piezoelectricity, piezomagnetism, and thermoelasticity. Analytical expressions are derived for the effective properties of a functionally graded transversely isotropic METE multilayer composite. The effects of functional gradation on the pyroelectric and pyromagnetic coefficients are numerically evaluated. It is shown that both the pyroelectric and pyromagnetic coefficients can be significantly enhanced (more than two times) by functional gradation, and the relative volume fractions at which these coefficients are maximized tend to extreme values. It is thus demonstrated that the present method can be used in the design of multilayered METE composites for the purpose of achieving a maximum energy conversion or transduction capability.

Study of structural, dielectric and magnetic behaviour of Ni0.75Zn0.25Fe2O4–Ba(Ti0.85Zr0.15)O3composites

“…There is a mechanical coupling between the magnetostrictive phase and piezoelectric phase [9,10]. The ME composites prepared by combining such phases in proper molar proportions have been observed to yield higher ME output as compared to single phase compounds and seem to be quite promising from an application point of view such as in large area magnetic field sensors and four state memory devices [11]. In the context of piezoelectric-magnetostrictive composites, the so-called product property [2] shows a nonlinear magnetoelectric (ME) effect which makes it difficult to use in linear devices.…”

The electric, magnetic, and elastic fields in damaged thermo-electro-magneto-elastic composites created by heat flow

“…The poling direction of both materials is oriented in the x 3 -direction. It should be mentioned that the pyromagnetic constant of the CoFe 2 O 4 is not available in the literature and some authors chose it to be equal to zero, see Tang and Yu (2009), Challagulla and Georgiades (2011), and Kim et al (2012), for example. In this article, the value of the slope of the magnetic flux with respect to temperature d B /d θ = 0.01 T/K has been determined from Figure 9 of Naiden et al (2008) at room temperature.…”

Size-Dependent Thermoelastic Behavior Analysis of Functionally Graded Magneto-Electro-Elastic Cylindrical Shells Based on Modified Couple Stress Theory

“…Tey showed that the sheet's vertical and transverse shear stresses could be studied as degrees of freedom by considering the mechanical deformation components and electrical and magnetic potentials. Using Lord-Schulman's theory to analyze the electro-magneto-thermoplastic response of thermoplastic magneto-electro-elastic (TMEE), a hollow cylinder made of magneto-electro-elastic (MEE) functionally graded material was used by Abbas and Zenkour [32] to study the efect of comfort time, temperature, and volume fraction of each phase on the static parameters of a smart-graded hollow cylinder. Tis study is presented as a guide for the Termoelastic magneto-electro-elastic (TMEE) response of smart materials under the heat source infuence.…”