Method for preparing electrically-fused barium zirconate

Abstract

The invention discloses a method for preparing electrically-fused barium zirconate. The method comprises the following steps: 1: putting powdery and granular monoclinic zirconia and any one of ceriumoxide or cerium carbonate into a mixer, uniformly mixing to form a mixture; 2: putting the mixture into an electric arc, fusing and refining at the temperature of 2600-3000 DEG C till the mixture is fully fused into a molten state; 3: naturally cooling the mixture in the molten state to below 50 DEG C to form an offwhite solid finished product; and 4: breaking the offwhite solid finished product into pieces, selecting and crushing to form barium zirconate powder. The method disclosed by the invention has the beneficial effects that the powder which is all barium zirconate phase is obtained through an electrofusion method and has the characteristics that the porosity is low, the volume density is high, particles of various particle sizes and fine powder can be processed, the high temperature volume stability is good and the like; and the problems that the prepared barium zirconate powder is low in purity and contains unreacted barium carbonate phases are solved.

Description

technical field [0001] The invention relates to the field of preparation methods of special refractory materials, in particular to a preparation method of fused barium zirconate. Background technique [0002] Barium zirconate (BaZrO 3 ) is an inorganic material with a cubic perovskite structure, with a lattice constant of 0.4913nm. Among all perovskites, barium zirconate has the largest lattice constant; the coefficient of thermal expansion is very small, between 20°C and 1080°C, The coefficient of thermal expansion is only 7.72×10 -6 / °C; thermal conductivity is low, melting point is as high as 2600°C, and phase change is not easy to occur. It has good mechanical and structural stability in extreme thermal environments and harsh environments. At the same time, barium zirconate also has very high chemical stability and thermal shock. and good thermal shock resistance. Barium zirconate is not only the preferred choice for high-temperature proton conductor materials, but al...

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Problems solved by technology

Barium zirconate powder prepared by hydrothermal method can be seen from the XRD analysis that there are obvious barium carbonate diffraction peaks, indicating that the prepared powder is not high in purity and contains unreacted barium carbonate phase

[0004] Barium zirconate powder is synthesized by solid phase method, and the publication number is CN201110350464, which is used for titanium alloy smelting barium zirconate refractory material and its preparation method for crucible. The molar ratio of coordination is BaCO 3 : ZrO 2 =1:1; in addition, add 0.5~5.0mol% TiO 2 ; This batch material is repeatedly sintered at a temperature of 1200-1400 ° C to make a barium zirconate refractory ", and then add 0.5-5.0 mol% of TiO 2 It is bound to produce barium titanate and zirconium titanate and undecomposed barium carbonate, and the purity of barium zirconate produced by this method is not high

[0005] At present, the barium zirconate powder prepared by hydrothermal method and solid phase method, the content of barium zirconate is less than 100% by XRD analysis, and there are obvious barium carbonate diffraction peaks, indicating that the purity of the prepared powder is not high

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