Electrophysical properties of the multiferroic PFN–ferrite composites obtained by spark plasma sintering and classical technology

The multiferroic (ferroelectric–ferromagnetic) composites (PFN–ferrite) based on ferroelectromagnetic PbFe 1/2 Nb 1/2 O 3 powder and ferrite powder (zinc–nickel ferrite, NiZnFeO 4 ) were obtained in the presented study. The ceramic PFN–ferrite composites consisted of 90% powder PFN material and 10% powder NiZnFeO 4 ferrite. The ceramic powders were synthesized by the classical technological method using powder calcination, while densification of the composite powders (sintering) was carried by two different methods: (1) free sintering method (FS) and (2) spark plasma sintering (SPS). The composite PFN–ferrite samples were thermally tested, including DC electrical conductivity and dielectric properties. Besides, XRD, SEM, EDS (energy-dispersive spectrometry) and ferroelectric properties (hysteresis loop) of the composite samples were tested at room temperature. At the work, a comparison was made for the results measured for PFN–ferrite composite samples obtained by two methods. The X-ray examination of multiferroic ceramic composites confirmed the occurrence of the strong diffraction peaks derived from ferroelectric (PFN) matrix of composite as well as weak peaks induced by the ferrite component. At the same time, the studies showed the absence of other undesired phases. The results presented in this work revealed that the ceramic composite obtained by two different technological sintering methods (free sintering method and spark plasma sintering technique) can be the promising materials for functional applications, for example, in sensors for magnetic and electric fields.