Preparation And Characterization Of Dop-stabilized Tetragonal Zirconia Ceramics

In the present paper,a novel way named polacrylamide gel method was employed to prepare Y-TZP(Tetragonal zirconia polycrystals stabilized by Y₂O₃) powder at low temperature.Effects of the heat-treatment temperature and the stabilizer content of zirconia powder phase were evaluated.The results and development are as follows:(1) Preparation and characterization of 3Y-TZP.Powder was heat-treated at 600℃to remove organic compounds and water,and then,powder was heat-treated at 700℃,800℃,1000℃,1200℃,respectively.Determined the best experimental conditions:metal ions concentration is 0.3 mol/L,citric acid concentration is charge mole content of metal ions,ratio of monomer and lattice reagent is 12:1,volume ratio of catalyst and initiator is 10:1,pH is controlled at 4～5,xerogel is heat-treated at 600℃.(2) Preparation and characterization of different stabilizer stabilized zirconia ceramics nanopowder.Their mechanical properties were also charactered.The different stabilizer leads to different phase,part of stabilizer appeared monoclinic,UV—Vis of different stabilizer is different,structure change aroused different ionic radius is different,mechanical properties of different stabilizer stabilized zirconia ceramics is different,they can be applied to different field.(3) Preparation and characterization of 0.5%Gd₂O₃ doping ZrO₂ and 0.5% Gd₂O₃ doping 3Y-TZP nanopowder.Mechanical properties and morphology of the zirconia ceramics samples were charactered.XRD analysis shows that the diffraction peak with the increase of temperature are enhanced,crystal form becomes integrity, with the increase of temperature phase grain grows,and agglomeration becomes obvious,at 1200℃the powder is sintered,but particle size is in nanometer.In addition,0.5%Gd₂O₃ doping 3Y-TZP powder,with the increase of stabilizer content, the diffraction peaks become roundness.Relative density of green body is 39%, relative density of sinter is 85%,and volume shrinkage is 10%,so mechanical properties is non-ideal,it should be improved.Analysis of surface phase of zirconia ceramics shows that main phase is tetragonal zirconia polycrystals,and there is a little monoclinic,surface morphology is better and smooth,particles is compact,and crystal form is integrity.Section morphology shows that stomata content is more, density is non-ideal,it is a factors that leads to mechanical properties low.