Published online by Cambridge University Press: 16 February 2011
A non-isothermal analysis of grain growth in tetragonal zirconia ceramics doped with various amounts of yttria and/or ceria in the temperature range 700–1150°C is presented. In these nanocrystalline ceramics, prepared by the gel precipitation technique, two grain growth regimes are recognized. At temperatures up to 900–1000°C grain growth proceeds slowly at high values of porosity (55%→35%); probably by means of a surface diffusion mechanism. At higher temperatures grain growth is much faster and occurs in locally dense regions by a normal grain growth or an impurity drag mechanism. Apparent activation energies are given for five compositions in both regimes.
The isothermal sintering behavior of 3 mol% Y2O3-containing TZP at 1050°C is analysed. A dense ceramic with a crystallite size in the nanometer regime (< 100nm) is obtained.