Electrophysical Properties of PMN-PT-Ferrite Ceramic Composites.

Bochenek Bochenek,Brzezińska Brzezińska,Skulski Skulski,Niemiec Niemiec

doi:10.3390/ma12203281

Abstract

Ferroelectromagnetic composites based on (1−x)PMN-(x)PT (PMN-PT) powder and Ni-Zn ferrite powder were obtained and are described in this work. As a ferroelectric component, we used (1−x)PMN-(x)PT solid solution (with x = 0.25, 0.28, 0.31, 0.34, 0.37, 0.40), synthesized using the sol-gel method. As a magnetic component, we used nickel-zinc ferrite, obtained using classic ceramic technology. The six compositions of PMN-PT used have rhombohedral symmetry, tetragonal one and mixture of these phases (morphotropic phase area), depending on x. The final ceramic composite samples were obtained using the classic methods involving the calcination route and pressureless final sintering (densification). The properties of the obtained ceramic composite samples were investigated, including microstructure SEM (scanning electron microscope), dielectric properties, electromechanical properties, and DC (Direct Current) electrical conductivity. Results showed that the microstructures of the PP-F composite samples characterized by larger grains were better crystallized, compared with the microstructures of the PMN-PT ceramic samples. The magnetic properties do not depend on the ferroelectric component of the composite samples, while the insertion of ferrite into the PMN-PT compound reduces the values of remnant and spontaneous polarization, as well as the coercive field. The dielectric measurements also indicated that the magnetic subsystem influences the dielectric properties. The present results show that the PP-F ceramic composite has good dielectric, magnetic, and piezoelectric properties, which predisposes this type of material to specific applications in microelectronics and micromechatronics.

Highlights

In previous work [34], the authors described ceramic composites based on two compositions of PMN-PbTiO3 component (PT), i.e., 0.72PbMg1/3 Nb2/3 O3 -0.28PbTiO3 with rhombohedral symmetry and
The PMN-PT has rhombohedral symmetry, tetragonal symmetry, and a mixture of these two phases that determine the electrophysical properties of the materials
The energy dispersive spectrometer (EDS) tests confirmed the assumed chemical composition of PT ceramic samples (PP)-F and the presence of maxima from elements originating in PMN-PT, as well as elements originating in ferrite [35]

Summary

Introduction

There has been a global search for multiferroics [1,2,3,4], magnetoelectric materials [5], materials with coupling between magnetic and polarization orders [6], materials with functional properties [7,8] in the form of magnetoelectric composites [9,10,11,12,13], lead-free multiferroic composites [14,15], and multiferroic nanocomposites [16,17]. In previous work [34], the authors described ceramic composites based on two compositions of PMN-PT, i.e., 0.72PbMg1/3 Nb2/3 O3 -0.28PbTiO3 with rhombohedral symmetry and. In the composite samples obtained in such a way, XRD patterns, EDS spectra, as well as dielectric and magnetic properties were investigated [35]. The authors describe more detailed investigations of the electrophysical and magnetic properties as well as phase transitions of PMN-PT-ferrite ceramic composites with x = 0.25, 0.28, 0.31, 0.34, 0.37, 0.40 (i.e., the same as in Reference [26]). The following investigations were conducted: SEM microstructure, more detailed dielectric investigations, electromechanical properties, and DC (direct current) electrical conductivity

Experiment

Results and Discussion

Conclusions