Zinc oxide has been studied for many years and found many applications in different areas, including the power engineering, where the ZnO-based ceramics could be used as a varistor. However, there is a necessity to add different oxides to ZnO to make a uniform ceramics structure with well enough nonlinear characteristics. In this regard, the uniform distribution of additives in the structure of a composite based on ZnO becomes an urgent task to prepare the high-quality ceramics. This work shows the possibility to obtain the composite powdered material with the uniformly distributed Bi2O3 addition in the ZnO crystallites by a plasma dynamic method. The features of this method and flowing reactions allow forming the ZnO-Bi2O3 particles with the core-shell structure. The spark plasma sintering of the ZnO-Bi2O3 composite material with such particles structure provides the production of varistor ceramics characterized by a fine-grained ZnO structure (average grain size is about 1 µm) with uniformly filled intergranular spaces by Bi2O3. The comparison of voltage-current characteristics with the ceramics made of ball-milled commercial powders showed the prospects of using as-prepared ZnO-Bi2O3 composite with core-shell structure.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Process Chemistry and Technology
- Surfaces, Coatings and Films
- Materials Chemistry