The paper presents the technology of ferroelectric-ferromagnetic ceramic composites obtained from PLZT powder (the chemical formula Pb 0.98 La 0.02 (Zr 0.90 Ti 0.10) 0.995 O 3) and ferrite powder (Ni 0.64 Zn 0.36 Fe 2 O 4), as well as the results of X-ray powder-diffraction data (XRD) measurement, microstructure, dielectric, ferroelectric, and magnetic properties of the composite samples. The ferroelectric-ferromagnetic composite (P-F) was obtained by mixing and the synthesis of 90% of PLZT and 10% of ferrite powders. The XRD test of the P-F composite shows a two-phase structure derived from the PLZT component (strong peaks) and the ferrite component (weak peaks). The symmetry of PLZT was identified as a rhombohedral ferroelectric phase, while the ferrite was identified as a spinel structure. Scanning electron microscope (SEM) microstructure analysis of the P-F ceramic composites showed that fine grains of the PLZT component surrounded large ferrite grains. At room temperature P-F composites exhibit both ferroelectric and ferromagnetic properties. The P-F composite samples have lower values of the maximum dielectric permittivity at the Curie temperature and a higher dielectric loss compared to the PLZT ceramics, however, the exhibit overall good multiferroic properties.

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In the present paper, a model of wear mechanism of Al2O3/WS2 with polyether ether ketone (PEEK)/BG plastic has been presented. An amorphous Al2O3 oxide layer with a tungsten disulfide modifier has been characterized by the Scanning Electron Microscope equipped with an Energy Dispensive Spectrometer (SEM/EDS) and XRD analysis. The addition of WS2 to the acid bath reduces the friction coefficient of the Al2O3/WS2-PEEK/BG friction pair. The technology applied to receive the Al2O3/WS2 layer, with appropriately selected conditions, allows us to obtain a tribological layer that enables the delivery of WS2 solid lubricant during friction.

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