The Preparation Of Ultrafine Dy-doped TiO₂ And ZrO₂ Ceramic Powders

In this paper, the technics about the preparation of mixed TiO2 rare earth oxides and mixed ZrO2 rare earth oxides was studied. The power prepared was examined by many kinds of analytic measures, like as XRD, XPS, TEM, SEM and X rays fluorescence, etc.The sol-gel method was used to synthesize Dy-doped titanium oxide, the impact of elements such as solvent's quantities, temperature, PH value, calcination temperature on the course of sol-gel is studied, and the quantities of mixed rare earth is also studied on the influence about the structure of phase, thus established the best technology parameter. When the molar ratio of titanate, water and ethanol is 1: 2.5: 25, PH value is controlled about 4.0, calculation temperature as 600℃, and calcinations time is two hours, the ultrafine product is prepared.The temperature of polymorphic transition between anatase and rutile of Dy-doped TiO2 is higher than the temperature of transition of pure TiO2. The rare earth improves the hot stability of the power. Compared with 3%, the temperature of polymorphic transition between anatase and rutile of 8% which is the molar quantities of mixed rare earth is a little lower. The calcination temperature is a main reason which influences the structure of phase.The complexation approach applied with the addition of acetic acid complexing agent is used to synthsize Dy2O3/ZrO2 ceramic power under low temperature. The best heat treatment temperature is about 600℃. And how the PHvalue influence on the reacts is studied.Using continuous compacting progress Dy2O3/ZrO2 materials can be sintered at low temperature. 98.8% of theory density was obtained for ultrafine Dy2O3/ZrO2 ceramic power sintering at 1200℃, which is 400℃ lower than the sintering temperature of the common ceramic power. It studied theinfluence of sintering temperature on the crystalline grain of power by SEM.