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A method of fabricating ZrO₂-mullite composites based on plasma spraying of alumina and zircon mixtures has been proposed and developed (3Al₂O₃+2ZrSiO₄ = 2Al₂O₃·2SiO₂ +2ZrO₂). The feedstock is prepared by a combination of mechanical alloying which allows formation of fine grained, homogeneous solid solution mixtures and following plasma spheroidization that yields rapid solidified microstructures and enhanced compositional homogeneity. The homogeneity is further realized when the plasma spray coatings are formed at last, and mullite formation temperature is expected to decrease by the unique preparation technique adopted in this study. Microstructure of the coatings were studied using the transmission electron microscope (TEM), and the mechanical properties such as hardness and fracture toughness of the coatings were measured with the indentation technique. The relationship between the mechanical properties and microstructure were investigated.

Silicon carbide composite ceramic filtration membrane materials were prepared by air spray technology. In this process, using some organic solvents such as glycerol, ethanol, etc to fabricate a stable, excellent dispersibility inorganic silicon carbide slurry. Using air spray technology and coating the filter membrane. According to some heat treatments that sintering temperature from1350℃ to1450℃ for 3h, we can prepare a well-distributed, jumbo size SiC ceramic composite filtration membrane. The effects of particle size of SiC, sintering temperature, different ceramic binders on SiC filtration membrane were investigated. Meanwhile, the reaction bonding characteristics, phase composition, flexural strength as well as microstructure of SiC composite ceramics filtration membrane were also investigated. It is demonstrated that 22.8μm silicon carbide sintered at 1450℃ will obtain a better performance. With particle size increases, silicon carbide porous ceramic surface oxide layer thinner prepared at the same temperature. When 15wt% ceramic binder was added, a flexural strength of 36.6MPa was achieved at an open porosity of 35.3%. Al(OH)₃ used as a ceramic binder is very suitable due to its outstanding connectivity and better uniformity.