Erosion-resistant zirconium oxide nozzle bricks and preparation method thereof

Abstract

The invention discloses erosion-resistant zirconium oxide nozzle bricks and a preparation method thereof, and belongs to the technical field of refractory materials. The zirconium oxide nozzle bricksare prepared from the following raw materials in percentage by weight: 93 to 96 percent of electrically fused zirconia, 2 to 4 percent of lanthanum oxide fine powder and 2 to 3 percent of an adhesive.The preparation method comprises the following steps: (1) crushing the electrically fused zirconia sand, mixing the crushed electrically fused zirconia sand with the lanthanum oxide fine powder, finely grinding the mixture, and pressing the mixture to obtain green bricks; (2) performing preliminary calcining on the green bricks under a nitrogen atmosphere at 1,300 to 1,400 DEG C in a temperaturepreservation manner for 2 to 3 hours; (3) crushing the calcined green bricks, mixing the crushed calcined green bricks with 2 to 3 percent of the adhesive, finely grinding the mixture till 2,000 to 3,000 meshes are achieved, pressing the mixture into green bricks, and performing secondary calcining under the nitrogen atmosphere at 1,650 to 1,670 DEG C in a temperature preservation manner for 2 to4 hours, thereby obtaining final products which are the zirconium oxide nozzle bricks. According to the zirconium oxide nozzle bricks and the preparation method thereof which are provided by the invention, by calcining under the nitrogen atmosphere through a two-step method, impurity iron can be converted into iron nitride in situ, and the erosion resistance of the zirconium oxide bricks is enhanced, and the service life of the zirconium oxide bricks is prolonged.

Description

technical field [0001] The invention belongs to the technical field of refractory materials, and in particular relates to an erosion-resistant zirconia nozzle brick and a preparation method thereof. Background technique [0002] Zirconia nozzle is one of the important functional refractory materials used in continuous casting, which plays a role in controlling the flow of molten steel. The uniform and stable flow of molten steel into the mold through the nozzle is the key to ensure the continuous casting production and the quality of the slab. Therefore, the nozzle is required to have good corrosion resistance and thermal stability, and blockage, shedding, cracking and diameter expansion are not allowed during use. The expansion of the nozzle diameter not only leads to an increase in the amount of steel passing through, but also affects normal production. The fallen nozzle material is involved in the steel flow and easily forms non-metallic inclusions in the steel, which af...

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Problems solved by technology

Because the chemical activity of metal aluminum is very active, metal aluminum powder with very fine particle size cannot be used, which will easily affect the density of the skateboard due to the volatilization of metal aluminum

At the same time, due to the larger particles of aluminum powder, the dispersion effect is affected to a certain extent, so more additions are required