Sintering of tin oxide ceramic with additives

Abstract

In order to study the mechanism of activated sintering of tin dioxide and the role of the processes, the shrinkage kinetics of the composition (material) and the variation of diffusion parameters in the region of solid-phase interaction during heating in isothermal and nonisothermal (polythermal) schedules were studied. The tin dioxide used for this purpose was of analytical grade (GOST 22516-77). The specific surface of the powder was found to be 0.87 + 0.05 m2/g. The activators ZnO and Nb2Os, of ultrapure grade, were added to SnO2 up to 4% by weight during the process of dry grinding, which was carried out for 8 h. Specimens measuring I0 • i0 • i00 mm were compacted at a pressure of 30 MPa. As a temporary binder a 5% aqueous solution of polyvinyl alcohol was used. Apparent density and open porosity were determined according to GOST 2409-80. As the sintering parameter, the linear shrinkage y of the specimens was recorded. The kinetic parameters of polythermal sintering were calculated with the aid of a Mir-2 computer using the nonlinear method of least squares, and also by the method of simplex scan.