A Study On The Superfine ZrO₂ Powders Prepared By Low-Temperature Combustion Synthesis Technology

Superfine ZrO₂ powders has been widely used in electron industry, metallurgy, spaceflight, chemistry, environment, biology, medicine and so on., due to its merits such as large specific surface area, high surface activity, chemical reaction quick, fast velocity of dissolution, strong sintering body hardness, and specific electricity, magnetism and optical property. Science workers are very interested in study of superfine ZrO₂ powders, at the same time, preparation technology of superfine ZrO₂ powders has been one of top science study.Presently, physical and chemistry methods are primary preparation technology. It is very difficult for traditional methods to apply in production, owing to enormous energy waste, complicated craftwork, costly raw materials, long production period and so on. So it has important practical meaning for driving utility and industry of superfine ZrO₂ powders to tap a simple and applied preparation technology.Recently, as a novel technology for the preparation of oxidate powders with superfine, the solution combustion method has been gotten considerable attentions. In this paper, the technology was applied to preparing superfine ZrO₂ powders. Morphology of particle and grain size distribution under different processing parameters are characterized by the means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM).The results indicate that the particle morphology, grain size are considerably influenced by processing parameters. When mol ratio of urea and metal nitrate is1:2, the sample is purer, crystallization perfection with 600℃furnace temperature and its average grain size is about 44.07nm. Added appropriate NH4NO3 can release more gas, optimize outcome peculiarities.Besides, the effects of additive PEG and calcining process on the synthesized powders were also investigated in this paper. The results show that both of the two parameters have some effects on the size, shape and conglomeration of the synthesized powders. When the content of PEG (4000+1000) is 2.0 wt%, the particles have nearly spherical shape, homogeneous and small size. Calcining temperature increase would be able to decrease organic compound slowly, lighten conglomeration of the synthesized powders, reduce powder activity. But when temperature is too high, powders has obvious sintering phenomenon. Particles evidently grow up along with calcining time prolonging. Therefore, when calcining process is 650℃for 1.5 hour, superfine ZrO₂ powders with none organic compound left , low conglomeration and grain size uniform can be obtained.