The Preparation Of ZrO₂ Nanopowders Used For Stereolithography Ceramic Slurry

Zirconia has excellent physical and chemical properties and biocompatibility, and get good mechanical and electrical properties after doping yttrium and magnesium.It is widely used in orthopedic, dental restorative material, solid electrolyte and sensors. However, the ceramic material is difficult to process, which limit its application, especially those with individuation,complicated surface,high surface quality of miniature ceramic device.Therefore,it is urge to develop new process of ceramic molding. In recent years, add material manufacturing technology develops rapidly, which is characterized in personality,in which the photolithography technology is the most promising new ceramic molding technology,as for its simple equipment, high precision, good surface quality. In order to obtain a high density,high loading capacity of slurry is inevitable, but higher loadings will reversely make the viscosity of the slurry is too large, poor fluidity, can not be printed. For the sake of obtaining the slurry with high solids content and low viscosity, we propose a new idea: preparing the slurry with such powders: particle surface is smooth, moderate size, lighter reunion and good mobility.Between commonly used methods of systhesis nano powder, hydrothermal method is low costing and easy to change the reaction conditions to adjust particle morphology and size. Therefore, the required zirconia powder was prepared by hydrothermal.Firstly, this paper synthesis ZrO₂ nano powders by hydrothermal,then discussed how the type of zirconium source?Zr OCl2, Zr?SO4?2, Zr?NO3?4 and Zr Cl4? and precipitant?Na₂CO₃, NH4HCO3, NH4HCO3, CO?NH2?2?, reaction temperature and reaction time,the concentration of SO₄^2- affect the phase structure morphology and particle size of ZrO₂ powder. and well dispersed, particle size of about 40 nm, surface smooth spherical ZrO₂ nanoparticles is prepared by adjusting the reaction system and the reaction parameters. And found that when used alcohol as the reaction medium, 2 4?m synthesized spherical ZrO₂ amorphous powder is obtained. When adding a certain concentration of SO₄^2-tetragonal-phase,flower-shaped ZrO₂ particles was obtained,while monoclinic rodlike ZrO₂ powders were obtained with higher concentration of SO₄^2-, the growth mechanism of different morphologies was discussed, the product prepared with 0.1M [SO₄^2-]has the best adsorption properties.Then,the paper prepared 3YSZ, 10 MSZ and 5Y5 MSZ, and explored how the precipitating agent concentration, hydrothermal time and temperature affect the phase structure, morphology and particle size of the doped powders. a narrow particle size distribution of about 30⁵0nm, smooth surface 3YSZ powder was prepared.Besides, the influence of calcined on the size of 10?Y+M?SZ powder particle size and the sintered properties of 3YSZ is discussed.For smaller particle size powder, calcining can improve its sintering properties.With the above 3YSZ powder, using 6 the polyurethane acrylate as prepolymer, tripropylene glycol diacrylate?using TPGDA? as a diluent, bis-phenyl phosphine oxide?819? as initiator, photolithography zirconia slurry was prepared. The paper studied on how the solid content and the amount of initiator affect the rheological properties and curing properties of the slurry. With the increasing solid content of the slurry viscosity increased significantly, the depth of curing reduces, curing speed slowed down, the cure shrinkage rate reduced, the density increases. Increasing the temperature and shear rate could significantly reduce the viscosity of the slurry, the viscosity of 35vol% slurry is less than that of 30vol% at high temperature and large shear rate.