Effect of ZrO2 additions on sintering of SnO2-based ceramics

The effect of zirconia additions on sintering of CoO doped tin dioxide has been investigated in the temperature range 1100–1250 °C. A first study showed that the substitution of tin by zirconium reduces significantly the volatilisation rate of SnO2 for temperatures greater than 1400 °C. It appeared that the zirconium content increase inhibits the densification kinetics of SnO2-based ceramics. Indeed, the relative density did not exceed 93% for a Zr content lower than 6 mol% in the Sn(1–x)ZrxO2 solid solution. This negative effect can be imputed to the elastic distortions caused by the introduction of Zr in the tin dioxide lattice. So, the diffusion rate of point defects such as oxygen or cobalt ions is lowered.