STUDY OF THE MICROSTRUCTURE AND PHASE FORMATION IN CERAMICS BASED ON Zn, Sn AND Ti OXIDES

Abstract

Ceramics was obtained from the mixture of ZnO, SnO2 and TiO2 nanopowders by the method of solid-state sintering at 1123 K and 1443 K. The indicated nanopowders are used as components in arc dampers and for dispersion-strengthening in silver-based electrical contact materials. The phase formation and microstructure of the obtained material were studied by the methods of scanning electron microscopy, energy dispersive microanalysis and X-ray phase analysis. It is shown that at a sintering temperature of 1123 K a dispersed structure was formed, with the size of the Zn2TiO4 and ZnO phases being 0.5 – 1.0 µm. The solid phase reactions in the system ZnO/TiO2 at Тsint = 1123 K resulted in the formation of two-phase ceramics ZnO/Zn2TiO4 with the residual amounts of the phases of zinc and tin oxides. At Тsint = 1443 K there occurred the grain growth, Zn2SnO4 became the predominant phase and there remained a certain amount of the zinc and tin oxide phases.