A kind of preparation method of corundum-zirconium mullite breathable brick with high thermal shock resistance

Abstract

The invention relates to a method for preparing a highly thermal-shock-resistant corundum-zirconium-mullite air-permeable brick. The invention uses phenolic resin to coat corundum particles, corundum particles and fine powder, zirconium-mullite particles and fine powder, and alumina Micropowder, silica micropowder, and hydrated alumina powder are used as raw materials, and high-efficiency water reducer is added. After dry mixing, water is added to mix into mud, which is poured into a mold to form a permeable brick body. After demoulding, curing and drying, it is prepared by high temperature treatment. Developed high thermal shock resistance corundum-zirconium mullite permeable bricks. It solves the shortcomings of poor thermal shock resistance and peeling resistance of current air-permeable brick materials. The high thermal shock resistance corundum-zirconium mullite breathable brick prepared by the present invention is expected to replace the current chrome corundum and corundum-spinel breathable brick materials for steelmaking, and has high blowing rate, good spalling resistance and High life characteristics.

Description

technical field [0001] The invention belongs to the technical field of inorganic non-metallic materials, and in particular relates to a method for preparing a corundum-zirconium mullite air-permeable brick with high thermal shock resistance. Background technique [0002] As the key functional element of the refining process outside the molten steel furnace, the ladle breathable brick is used to introduce a certain pressure of inert gas into the molten steel through the breathable brick to physically stir the molten steel to promote the convective movement of the molten steel to homogenize the temperature of the molten steel and the composition of the molten steel. Accelerating the metallurgical reaction and promoting the floating of inclusions plays an important role in the purification of molten steel. In recent years, the requirements for steel quality have become higher and higher, the melting temperature and melting time of ladles have been increased successively, and th...

AI Technical Summary

Problems solved by technology

There are a large number of interconnected pores of different sizes in the diffused air brick, which has high porosity and low strength.

When the blowing is stopped, the molten steel and steel slag in the ladle are easy to penetrate into the pores, and produce dense parts on the working surface of the breathable brick, causing the pores to be blocked; in addition, its high temperature strength is low during the oxygen burning process, and the corrosion is serious, and its service life fluctuates Very large, not conducive to smelting operations

The slit-type permeable brick has the advantages of stable blowing airflow, small reverse impact force, wide airflow adjustment range, compact brick body, and high strength. It is widely used in various domestic ladles. Stone slit-type ladle permeable bricks are compact and poor in thermal shock resistance, and are prone to cracks due to the influence of temperature gradients during use, resulting in thermal spalling of the brick body, or even direct fracture and damage, which greatly reduces the service life of the slit brick.

[0004] In order to improve the use effect of the current slit-type breathable bricks, many researchers have done a lot of work on the channel structure, ventilation mode, material and combination system of the breathable bricks, but the improved breathable bricks are still in service. Cross-cutting and peeling often occur, causing abnormal damage or even loss of function of the ventilation brick, and the end of life

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