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Zirconium oxychloride (ZrOCl2 · 8H2O) and yttrium oxide (Y2O3) as a starting material, by using ammonia (NH3 · H2O) is titrated prepared zirconium hydroxide sol, and the sol to replace the traditional agglomeration-type nano-powder liquid phase plasma spraying (SPPS) preparation of nano ZrO2/Y2O3 thermal barrier coatings. TEM, SEM, EDS, XRD, TG-DSC, VIDAS image analyzer, particle size analyzer, and TH310 Rockwell hardness tester test means or instruments to characterize the structure and properties of the colloidal coating. Zirconium oxychloride (ZrOCl2 · 8H2O) and yttrium oxide (Y2O3) was dissolved in deionized water or ethanol, and aqueous ammonia (NH3 · H2O) as a precipitating agent, while the process of hydrolysis and polycondensation: a dilute solution of Zr is mononuclear ZrO22 form exist; When [Zr4] gt; 10-3mol / L, [H] in the range of 0.75-1 mol / L, polymerization began to form polymer [Zr3 (OH) 4] 8. When [Zr4] was increased to 1.6 × 10-1mol / L, Zr is present in polynuclear complex form; if [H] lt; 0.75mol / L, it is converted to six polymers. When Zr4 or ZrO22 concentration is relatively high, Zr mainly the tetramer compound [of Zr4 (OH) 8 (H2O) 16] 8 exist, including Zr (IV), 2 bridge bond OH-ions and four water molecules. After gelation, the sol body gradually hydrolyzed and converted to irreversible gel [Zr4 (OH) 8-x (H2O) 2x · yH2O] n. Experimental analysis: a concentration of 0.8 mol / L, pH = 4 to 6, the micelle size of 80 to 100 nm in a sol of raw materials suitable for plasma spraying as the liquid phase; precursor concentration of 0.8 mol / L, jet distance 80 mm, the current strength 500A, voltage 80 V, the atomizing air pressure 0.4 MPa, the feed rate 120 g / min, the coating is mainly present in particulate form, TEM showed that the grain size is between 20-30 nm. Coating: SEM showed that the entire liquid sprayed layer organizational structure relatively uniform aggregates with the conventional plasma spraying powder preparation of the thermal barrier coating is not the same, no layered tissue emergence of this new type of thermal barrier coating, and the precursor the concentration of the solution, the solvent ratio, atomizing air pressure and feed rate are several important factors that affect the microstructure and properties of the coating. The porosity of the coatings prepared in the different precursor, under different process conditions, hardness, bonding strength and thermal shock properties. Liquid phase plasma nano-sprayed layer of thermal shock resistance than conventional coatings have increased significantly. Excellent thermal shock resistance of liquid phase ion nano-spray coating, and the coating microstructure great relationship. For the liquid phase and plasma spraying, when the power of 40 kW (500A × 80V), the concentration of the precursor solution was 0.8 mol / L, the spraying distance controlled at 80mm, the atomizing air pressure of 0.4 MPa, when the feed rate of 120g/min Preparation Nano coating microstructure and performance is relatively good.
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