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In this paper, ZrOCl2 · 8H2O, polyethylene glycol, glutaraldehyde and other raw materials, Y (NO3) 3.6 H2O as a dopant, NH3 · H2O as precipitant were used atmospheric and organic networks hydrothermal gel process Preparation of zirconium oxide nano powder, and finally by the granulation, the prepared dry pressing the powder into a green body pressed and sintered in atmospheric pressure sintering method, the sintering temperature discussed sintered body density, bending strength, and the ceramic micro- and compactness of the structure. While using X-ray diffraction spectrum (XRD) detects the phase composition of the powder; using transmission electron microscopy (TEM) study the powder morphology, size and distribution; thermogravimetry - differential thermal analysis (TG-DTA) determining the firing temperature of the gel powder; scanning electron microscope (SEM) analysis of the microstructure of the sintered body. Main work and made the following conclusions: 1. Pressure hydrothermal process of zirconium dioxide powders of various reaction conditions on the impact of zirconium dioxide, reaction time was changed during the experiment t = 2,3,5, 7 days, the reaction and the pH of the precursor concentration 8,9,10,11,12,13,14 0.1,0.3,0.4,0.5 mol / L, on the crystalline type crystal phase composition and grain size testing and analysis. At pH = 14, temperature of hot water 95 ℃, 3 days under the conditions of the reaction of the average particle size was prepared about 10nm, monoclinic phase coexist tetragonal phase zirconia powder;, and experiments show that increasing the concentration of the precursor zirconia powder to improve the yield. (2) Analysis of Organic Gel process polyethylene glycol concentration, crosslinker concentration and dosage as well as inorganic ions concentration ratio of the three network gel stability. With the increase of the concentration of polyethylene glycol and adding zirconium oxychloride increase the amount of gel crosslinking speed becomes faster, and reduce the concentration of the crosslinking agent directly affects the cross-linking effect. In 50ml, 2% of PVA was added to 30-40g of zirconium oxychloride and 10ml, 25% glutaraldehyde, by heating in a water bath 45 ℃ 10min precursor to form a stable gel, and the gel was allowed to stand and soak ammonia, dried and calcined at 600 ℃ for 2h to obtain uniform particle size, good dispersion, particle size of about 20nm of ZrO2 powders; simultaneously doped (Y3) experimental research results show that this method can prepare stable tetragonal zirconia nanopowders. 3 analyzes the different sintering density of the sample temperature, shrinkage, bending strength and scanning electron microscopy, organic network gel process is superior to the powder sintering pressure hydrothermal method, can achieve low-temperature sintering; doping After the sample sintered density, bending strength values ??are increased, that (Y3) the introduction of the grain growth can be suppressed to promote densification body.
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