Al2O3-SiO2 tundish permeable brick and preparation method thereof

Abstract

The invention relates to an Al2O3-SiO2 tundish permeable brick and a preparation method thereof. 65-78 wt% of tabular corundum particles, 7-20 wt% of mullite particles, 2-10 wt% of white corundum fine powder, 1-4 wt% of rho-Al2O3 fine powder, and 1-3 wt% of silicon micropowder are used as raw materials; 0.10-0.20 wt% of mixtures of sodium hexametaphosphate and sodium tripolyphosphate, 0.05-0.20 wt% of yellow dextrin, 0.01-0.20 wt% of azodicarbonamide, 1-4 wt% of Al2O3-SiO2 gel powder, and 0.20-1.0 wt% of aluminium fluoride are used as additives. The preparation method comprises the following steps: premixing the additives and silicon micropowder uniformly according to the contents, adding the tabular corundum particles and the mullite particles, mixing and grinding, adding the white corundum fine powder and rho-Al2O3 fine powder, mixing and grinding, adding 5-7 wt% of water, stirring, casting, molding, performing heat preservation at 110-200 DEG C for 12-48 hours, and finally sintering at 1200-1500 DEG C for 3 hours. The prepared permeable brick has good permeability and high strength, and is erosion-resistant and environment-friendly.

Description

technical field [0001] The invention belongs to Al 2 o 3 -SiO 2 Quality refractory technology field. Concretely involving an Al 2 o 3 -SiO 2 A tundish air-permeable brick and a preparation method thereof. Background technique [0002] With the development of tundish metallurgical technology, blowing inert gas into the molten steel for stirring through the breathable brick installed at the bottom of the tundish can not only effectively improve the flow of molten steel, prolong the residence time of molten steel, and promote the mixing of molten steel It is conducive to uniform temperature, and can use the generated micro-bubbles to capture inclusions, promote the floating and removal of inclusions, reduce the total oxygen content in molten steel, and facilitate the production of clean steel. Therefore, it is an important subject to develop a tundish diffused air brick with good air permeability, thermal shock stability, high strength and resistance to steel slag penetr...

AI Technical Summary

Problems solved by technology

However, the dry gel powder is not easy to disperse, the pores are unevenly distributed, there are still many large pores, and the steel slag is easy to penetrate and corrode, resulting in short life, and the introduction of whiskers also seals many through pores, and its efficiency needs to be improved.