Electrical and magnetic properties of the BF–PFN solid solutions obtained by spark plasma sintering method

Abstract

The paper presents the results of electrophysical tests of (1–x)BiFeO3-(x)PbFe1/2Nb1/2O3 (BF-PFN) solid solutions obtained by a combined technological process, i.e., calcination powders and spark plasma sintering (SPS). The structure, electric and magnetic properties, were performed for three BF-PFN samples (x = 0.4, 0.3, 0.2). A thorough analysis of Rietveld showed that all BF-PFN materials show perovskite structure with the coexistence of the main phases. The microstructure of the BF-PFN is of high quality, as well as dense, with well-developed grains and low porosity (improving the sinterability of the ceramic material), which shall be beneficial to the dielectric properties of the BF-PFN materials. At room temperature, the BF-PFN has both electrical and magnetic properties with medium values of permittivity (292 ÷ 1022), small dielectric loss tangent (0.032 ÷ 0.072) and high resistivity (1.2 ÷ 2.6 × 108 Ωm). At high temperatures, the BF-PFN samples reveal extremely high permittivity values, while the magnetic properties depend on the concentration of the PFN component.