Dense anti-crack electrically fused zirconia-alumina brick and preparation method thereof

Abstract

The application discloses a kind of dense anti-crack electric smelting zirconia corundum brick and preparation method thereof, belong to refractory material technical field, this dense anti-crack electric smelting zirconia corundum brick, including following raw materials, according to mass fraction: alumina 42.7~46.6%, zirconium dioxide 36.8~40.5%, silicon dioxide 11.5~14.2%, niobium pentoxide 2.5~4.4%, soda ash 0.7~1.1%, manganese dioxide 0.6~1% and copper oxide 0.5~1%, and by raw material mixing melting and oxygen carbon removal, molten liquid casting forming, annealing cooling preparation is obtained.The electric smelting zirconia corundum brick of the application has excellent density and anti-crack performance, greatly prolongs its service life.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of dense anti-crack electrically fused zirconia-corundum brick and its preparation method, belong to refractory technical field. BACKGROUND

[0002] With the development of glass industry, the requirement of refractory is also higher and higher, traditional refractory such as silica brick is no longer applicable when the temperature in kiln exceeds 1600 DEG C.In recent years, electrically fused zirconia-corundum brick develops fast, its high temperature resistance can reach above 1700 DEG C, and it is light in weight, is one of important refractory materials in modern glass melting furnace, and is usually applied in the most critical part of glass kiln.At present, domestic and foreign manufacturers have launched electrically fused zirconia-corundum brick with different zirconium contents.

[0003] Although electrically fused zirconia-corundum brick has many advantages, there are still some problems in practical application, such as insufficient anti-cracking performance, limited service life, etc., and it is necessary to further improve the density and anti-cracking performance of electrically fused zirconia-corundum brick to meet the demand of glass industry and other high-temperature industries for refractory, increase the market competitiveness and economic benefits of enterprises. SUMMARY

[0004] At least for one problem existing in the prior art, the present application provides a kind of dense anti-crack electrically fused zirconia-corundum brick, which has excellent density and anti-cracking performance, greatly prolongs its service life, and simultaneously provides a preparation method thereof.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: a kind of dense anti-crack electrically fused zirconia-corundum brick, comprising the following raw materials, in terms of mass fraction: alumina 42.7-46.6%, zirconium dioxide 36.8-40.5%, silicon dioxide 11.5-14.2%, niobium pentoxide 2.5-4.4%, soda ash 0.7-1.1%, manganese dioxide 0.6-1% and copper oxide 0.5-1%;

[0006] The alumina is composed of alumina with particle size of 200-300 nm and alumina with particle size of 25-50 μm;

[0007] The zirconium dioxide is composed of zirconium dioxide with particle size of 50-100 nm and zirconium dioxide with particle size of 50-100 μm;

[0008] The particle size of the silicon dioxide is 100-200 nm.

[0009] Preferably, in the alumina: the mass fraction of alumina with particle size of 25-50 μm in alumina with particle size of 200-300 nm is 25-30%, and in the zirconium dioxide: the mass fraction of zirconium dioxide with particle size of 50-100 μm in zirconium dioxide with particle size of 50-100 nm is 20-25%.

[0010] Preferably, the dense anti-crack electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 44.5% of alumina, 38.1% of zirconium dioxide, 12.2% of silicon dioxide, 3.1% of niobium pentoxide, 0.9% of soda ash, 0.7% of manganese dioxide and 0.6% of copper oxide.

[0011] Preferably, in the alumina: the mass fraction of alumina with a particle size of 25-50 μm accounts for 28.2% of the alumina with a particle size of 200-300 nm; and in the zirconium dioxide: the mass fraction of zirconium dioxide with a particle size of 50-100 μm accounts for 22.5% of the zirconium dioxide with a particle size of 50-100 nm.

[0012] The application further provides a preparation method of the dense anti-crack electrically fused zirconia-corundum brick.

[0013] (1) grinding alumina, zirconium dioxide and silicon dioxide to a required particle size, and then uniformly mixing the alumina, the zirconium dioxide and the silicon dioxide with soda ash, niobium pentoxide, manganese dioxide and copper oxide to obtain a mixture;

[0014] (2) pouring the mixture into an electric arc furnace, melting the mixture into a molten liquid at a temperature of 1890-1910 ℃, continuously heating to 2730-2750 ℃, and then performing oxygen blowing treatment to remove carbon oxide from the molten liquid to obtain a molten material liquid;

[0015] (3) casting the molten material liquid into a specially designed product mold, and annealing and cooling the molten material liquid in stages at different cooling rates to obtain the dense anti-crack electrically fused zirconia-corundum brick.

[0016] Preferably, the time for the heat preservation and the oxygen blowing treatment in step (2) is 20-25 min.

[0017] Preferably, the temperature of the molten material liquid is 2600-2650 ℃ when casting in step (3).

[0018] Preferably, the annealing and cooling in step (3) are performed in stages at different cooling rates: the annealing starting temperature is 2020-2100 ℃, the temperature is first decreased to 1350-1420 ℃ at a rate of 20-30 ℃ / h, then decreased to 950-1015 ℃ at a rate of 40-50 ℃ / h, and then decreased to 410-460 ℃ at a rate of 20-30 ℃ / h, and then naturally cooled.

[0019] Preferably, the annealing starting temperature is 2020-2100 ℃ and the heat preservation time is 90-120 min, and the temperature is decreased to 1350-1420 ℃ and the heat preservation time is 60-90 min.

[0020] The electrically fused zirconia corundum brick has excellent compactness and crack resistance, can significantly prolong the service life of the refractory material, and can further delay the generation and expansion of cracks, improve the high-temperature resistance, corrosion resistance and thermal shock resistance, thereby reducing the operation and maintenance, updating cost of the glass kiln, and improving the economic benefit of the enterprise. DETAILED DESCRIPTION

[0021] The following is a clear and complete description of the technical solutions in the implementation of the present application. The described embodiments are only a part of the embodiments of the present application, not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application. If the specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments, components used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0022] The purity of the soda ash in the present application is not less than 99.5%; the purity of the zirconium dioxide is not less than 99.5%; the purity of the aluminum oxide is not less than 99.0%; and the purity of the silicon dioxide is 98-99%.

[0023] Embodiment 1

[0024] A compact and crack-resistant electrically fused zirconia corundum brick comprises the following raw materials in terms of mass fraction: 35.04% of aluminum oxide with a particle size of 200-300 nm, 8.76% of aluminum oxide with a particle size of 25-50 μm, 26.25% of zirconium dioxide with a particle size of 50-100 nm, 11.25% of zirconium dioxide with a particle size of 50-100 μm, 11.5% of silicon dioxide with a particle size of 100-200 nm, 4.4% of niobium pentoxide, 0.8% of soda ash, 0.7% of manganese dioxide, and 0.6% of copper oxide.

[0025] The specific process of the preparation method is as follows:

[0026] (1) The aluminum oxide, zirconium dioxide and silicon dioxide are ground to the required particle size, and then mixed uniformly with the soda ash, niobium pentoxide, manganese dioxide and copper oxide to obtain a mixture;

[0027] (2) Pour the mixture into an electric arc furnace, melt into a molten liquid at a temperature of 1890-1910 DEG C, continue to heat to 2730 DEG C, then keep the temperature for 25 minutes and carry out oxygen blowing at the same time, oxidize and remove carbon from the liquid, and obtain a molten liquid;

[0028] (3) Pour the molten liquid at a pouring temperature of 2650 DEG C into a specially designed product mold to form solid-state electrically fused bricks, then anneal and cool, the annealing starting temperature is 2050 DEG C, keep the temperature for 110 minutes, then decrease the temperature to 1370 DEG C at a rate of 20-30 DEG C / h, keep the temperature for 85 minutes, then decrease the temperature to 1015 DEG C at a rate of 40-50 DEG C / h, then decrease the temperature to 460 DEG C at a rate of 20-30 DEG C / h, and then naturally cool to obtain dense and crack-resistant electrically fused zirconia corundum bricks.

[0029] Example 2

[0030] A dense and crack-resistant electrically fused zirconia corundum brick comprises the following raw materials in terms of mass fraction: 30.29% of alumina with a particle size of 200-300 nm, 16.31% of alumina with a particle size of 25-50 μm, 31.45% of zirconia with a particle size of 50-100 nm, 5.55% of zirconia with a particle size of 50-100 μm, 11.7% of silica with a particle size of 100-200 nm, 2.6% of niobium pentoxide, 0.8% of soda ash, 0.7% of manganese dioxide, and 0.6% of copper oxide.

[0031] The specific process of the preparation method is completely same as that of Example 1.

[0032] Example 3

[0033] A dense and crack-resistant electrically fused zirconia corundum brick comprises the following raw materials in terms of mass fraction: 17.08% of alumina with a particle size of 200-300 nm, 25.62% of alumina with a particle size of 25-50 μm, 16.2% of zirconia with a particle size of 50-100 nm, 24.3% of zirconia with a particle size of 50-100 μm, 12.5% of silica with a particle size of 100-200 nm, 2.5% of niobium pentoxide, 0.7% of soda ash, 0.6% of manganese dioxide, and 0.5% of copper oxide.

[0034] The specific process of the preparation method is completely same as that of Example 1.

[0035] Example 4

[0036] A dense anti-crack electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 29.89% of alumina with a particle size of 200-300 nm, 12.81% of alumina with a particle size of 25-50 microns, 31.59% of zirconia with a particle size of 50-100 nm, 8.91% of zirconia with a particle size of 50-100 microns, 12.5% of silica with a particle size of 100-200 nm, 2.5% of niobium pentoxide, 0.7% of soda ash, 0.6% of manganese dioxide and 0.5% of copper oxide;

[0037] The specific process of the preparation method is completely same as that of Example 1.

[0038] Example 5

[0039] A dense anti-crack electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 31.39% of alumina with a particle size of 200-300 nm, 11.61% of alumina with a particle size of 25-50 microns, 27.6% of zirconia with a particle size of 50-100 nm, 9.2% of zirconia with a particle size of 50-100 microns, 14.2% of silica with a particle size of 100-200 nm, 3.2% of niobium pentoxide, 1.1% of soda ash, 0.9% of manganese dioxide and 0.8% of copper oxide;

[0040] The specific process of the preparation method is completely same as that of Example 1.

[0041] Example 6

[0042] A dense anti-crack electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 32.85% of alumina with a particle size of 200-300 nm, 10.95% of alumina with a particle size of 25-50 microns, 30% of zirconia with a particle size of 50-100 nm, 7.5% of zirconia with a particle size of 50-100 microns, 11.5% of silica with a particle size of 100-200 nm, 4.4% of niobium pentoxide, 0.8% of soda ash, 1% of manganese dioxide and 1% of copper oxide;

[0043] The specific process of the preparation method is as follows:

[0044] (1) The alumina, zirconia and silica are ground to the required particle size, and then mixed with the soda ash, niobium pentoxide, manganese dioxide and copper oxide uniformly to obtain a mixture;

[0045] (2) The mixture is poured into an electric arc furnace, melted into a molten liquid at a temperature of 1890-1910 ℃, and then heated to 2740 ℃, and then kept for 22 min while oxygen blowing is carried out to remove carbon oxide from the liquid to obtain a molten liquid;

[0046] (3) the above molten liquid with a pouring temperature of 2630°C is formed into solid electrically fused bricks, which are then annealed and cooled, the annealing starting temperature is 2100°C, and the temperature is kept for 90 min, then the temperature is decreased to 1350°C at a rate of 20-30°C / h, and the temperature is kept for 90 min, then the temperature is decreased to 950°C at a rate of 40-50°C / h, and the temperature is kept for 90 min, then the temperature is decreased to 410°C at a rate of 20-30°C / h, and then the bricks are naturally cooled, to obtain the dense and crack-resistant electrically fused zirconia-corundum bricks.

[0047] Example 7

[0048] A dense and crack-resistant electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 33.552% of alumina with a particle size of 200-300 nm, 13.048% of alumina with a particle size of 25-50 μm, 28.86% of zirconia with a particle size of 50-100 nm, 8.14% of zirconia with a particle size of 50-100 μm, 11.7% of silica with a particle size of 100-200 nm, 2.6% of niobium pentoxide, 0.8% of soda ash, 0.7% of manganese dioxide and 0.6% of copper oxide.

[0049] The specific process of the preparation method is as follows:

[0050] (1) the alumina, zirconia and silica are ground to the required particle size, and then mixed with the soda ash, niobium pentoxide, manganese dioxide and copper oxide uniformly to obtain a mixture;

[0051] (2) the above mixture is poured into an electric arc furnace, and melted into a molten liquid at a temperature of 1890-1910°C, and then heated to 2750°C, and kept for 20 min while oxygen blowing is performed to remove carbon oxides from the liquid, to obtain a molten liquid;

[0052] (3) the above molten liquid with a pouring temperature of 2600°C is formed into solid electrically fused bricks, which are then annealed and cooled, the annealing starting temperature is 2020°C, and the temperature is kept for 120 min, then the temperature is decreased to 1420°C at a rate of 20-30°C / h, and the temperature is kept for 60 min, then the temperature is decreased to 980°C at a rate of 40-50°C / h, and the temperature is kept for 90 min, then the temperature is decreased to 440°C at a rate of 20-30°C / h, and then the bricks are naturally cooled, to obtain the dense and crack-resistant electrically fused zirconia-corundum bricks.

[0053] Example 8

[0054] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 31.968% of alumina with a particle size of 200-300 nm, 112.432% of alumina with a particle size of 25-50 μm, 29.718% of zirconia with a particle size of 50-100 nm, 8.382% of zirconia with a particle size of 50-100 μm, 12.2% of silicon dioxide with a particle size of 100-200 nm, 3.1% of niobium pentoxide, 0.9% of soda ash, 0.7% of manganese dioxide and 0.6% of copper oxide;

[0055] The specific process of the preparation method is completely same as that of Example 7.

[0056] Example 9

[0057] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 37.8792% of alumina with a particle size of 200-300 nm, 12.5208% of alumina with a particle size of 25-50 μm, 29.5275% of zirconia with a particle size of 50-100 nm, 8.5725% of zirconia with a particle size of 50-100 μm, 12.2% of silicon dioxide with a particle size of 100-200 nm, 3.1% of niobium pentoxide, 0.9% of soda ash, 0.7% of manganese dioxide and 0.6% of copper oxide;

[0058] The specific process of the preparation method is completely same as that of Example 7.

[0059] Example 10

[0060] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 31.08% of alumina with a particle size of 200-300 nm, 13.32% of alumina with a particle size of 25-50 μm, 28.575% of zirconia with a particle size of 50-100 nm, 9.525% of zirconia with a particle size of 50-100 μm, 12.2% of silicon dioxide with a particle size of 100-200 nm, 3.1% of niobium pentoxide, 0.9% of soda ash, 0.7% of manganese dioxide and 0.6% of copper oxide;

[0061] The specific process of the preparation method is completely same as that of Example 7.

[0062] Example 11

[0063] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 31.968% of alumina with a particle size of 200-300 nm, 112.432% of alumina with a particle size of 25-50 μm, 29.718% of zirconia with a particle size of 50-100 nm, 8.382% of zirconia with a particle size of 50-100 μm, 12.2% of silicon dioxide with a particle size of 100-200 nm, 3.1% of niobium pentoxide, 0.9% of soda ash, 0.7% of manganese dioxide and 0.6% of copper oxide;

[0064] The specific process of the preparation method is the same as that in Example 5, except that (3) the molten liquid with a pouring temperature of 2650°C is cast in a specially designed product mold to form a solid-state electrically fused brick, which is then annealed and cooled, with an annealing starting temperature of 2050°C, and a cooling rate of 20-30°C / h to 1370°C, then a cooling rate of 40-50°C / h to 1015°C, then a cooling rate of 20-30°C / h to 460°C, and then natural cooling, to obtain the dense and crack-resistant electrically fused zirconia-corundum brick.

[0065] Example 12

[0066] A dense and crack-resistant electrically fused zirconia-corundum brick, which comprises the following raw materials in terms of mass fraction: 31.974% of alumina with a particle size of 200-300 nm, 11.826% of alumina with a particle size of 25-50 μm, 27% of zirconia with a particle size of 50-100 nm, 9% of zirconia with a particle size of 50-100 μm, 14.2% of silica with a particle size of 100-200 nm, 3.2% of niobium pentoxide, 1.1% of soda ash, 0.9% of manganese dioxide, and 0.8% of copper oxide.

[0067] The specific process of the preparation method is the same as that in Example 9, except that (3) the molten liquid with a pouring temperature of 2640°C is cast in a specially designed product mold to form a solid-state electrically fused brick, which is then annealed and cooled, with an annealing starting temperature of 2010°C, and a cooling rate of 20-30°C / h to 1390°C, then a cooling rate of 40-50°C / h to 990°C, then a cooling rate of 20-30°C / h to 450°C, and then natural cooling, to obtain the dense and crack-resistant electrically fused zirconia-corundum brick.

[0068] Comparative Example 1

[0069] A dense and crack-resistant electrically fused zirconia-corundum brick, which comprises the following raw materials in terms of mass fraction: 31.974% of alumina with a particle size of 200-300 nm, 11.826% of alumina with a particle size of 25-50 μm, 27% of zirconia with a particle size of 50-100 nm, 9% of zirconia with a particle size of 50-100 μm, 14.2% of silica with a particle size of 100-200 nm, 3.2% of niobium pentoxide, 1.1% of soda ash, 0.9% of manganese dioxide, and 0.8% of copper oxide.

[0070] The specific process of the preparation method is the same as that in Example 5.

[0071] Comparative Example 2

[0072] A dense and crack-resistant electrically fused zirconia-corundum brick, which comprises the following raw materials in terms of mass fraction: 29.89% of alumina with a particle size of 200-300 nm, 12.81% of alumina with a particle size of 25-50 μm, 31.98% of zirconia with a particle size of 50-100 nm, 9.02% of zirconia with a particle size of 50-100 μm, 12% of silica with a particle size of 100-200 nm, 2.5% of niobium pentoxide, 0.7% of soda ash, 0.6% of manganese dioxide, and 0.5% of copper oxide.

[0073] The specific process of the preparation method is the same as that in Example 4.

[0074] Comparative Example 3

[0075] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 29.89% of alumina with a particle size of 200-300 nm, 12.81% of alumina with a particle size of 25-50 μm, 31.59% of zirconia with a particle size of 50-100 nm, 8.91% of zirconia with a particle size of 50-100 μm, 12.7% of silica with a particle size of 100-200 nm, 2.3% of niobium pentoxide, 0.7% of soda ash, 0.6% of manganese dioxide and 0.5% of copper oxide.

[0076] The specific process of the preparation method is completely same as that of Example 4.

[0077] Comparative Example 4

[0078] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 32.85% of alumina with a particle size of 200-300 nm, 10.95% of alumina with a particle size of 25-50 μm, 29.84% of zirconia with a particle size of 50-100 nm, 7.46% of zirconia with a particle size of 50-100 μm, 11.5% of silica with a particle size of 100-200 nm, 4.6% of niobium pentoxide, 0.8% of soda ash, 1% of manganese dioxide and 1% of copper oxide.

[0079] The specific process of the preparation method is completely same as that of Example 6.

[0080] Comparative Example 5

[0081] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 32.85% of alumina with a particle size of 200-300 nm, 10.95% of alumina with a particle size of 25-50 μm, 37.5% of zirconia with a particle size of 50-100 nm, 11.5% of silica with a particle size of 100-200 nm, 4.4% of niobium pentoxide, 0.8% of soda ash, 1% of manganese dioxide and 1% of copper oxide.

[0082] The specific process of the preparation method is completely same as that of Example 6.

[0083] Comparative Example 6

[0084] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 32.85% of alumina with a particle size of 200-300 nm, 10.95% of alumina with a particle size of 25-50 μm, 37.5% of zirconia with a particle size of 50-100 μm, 11.5% of silica with a particle size of 100-200 nm, 4.4% of niobium pentoxide, 0.8% of soda ash, 1% of manganese dioxide and 1% of copper oxide.

[0085] The specific process of the preparation method is completely same as that of Example 6.

[0086] Comparative Example 7

[0087] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: alumina with a particle size of 200-300 nm 43.8%, zirconium dioxide with a particle size of 50-100 nm 30%, zirconium dioxide with a particle size of 50-100 μm 7.5%, silicon dioxide with a particle size of 100-200 nm 11.5%, niobium pentoxide 4.4%, soda ash 0.8%, manganese dioxide 1%, and copper oxide 1%.

[0088] The specific process of the preparation method is completely same as that of Example 6.

[0089] Comparative Example 8

[0090] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: alumina with a particle size of 25-50 μm 43.8%, zirconium dioxide with a particle size of 50-100 nm 30%, zirconium dioxide with a particle size of 50-100 μm 7.5%, silicon dioxide with a particle size of 100-200 nm 11.5%, niobium pentoxide 4.4%, soda ash 0.8%, manganese dioxide 1%, and copper oxide 1%.

[0091] The specific process of the preparation method is completely same as that of Example 6.

[0092] Comparative Example 9

[0093] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: alumina with a particle size of 200-300 nm 31.08%, alumina with a particle size of 25-50 μm 13.32%, zirconium dioxide with a particle size of 50-100 nm 28.575%, zirconium dioxide with a particle size of 50-100 μm 9.525%, silicon dioxide with a particle size of 100-200 nm 12.9%, niobium pentoxide 4.4%, soda ash 0.9%, and copper oxide 0.6%.

[0094] The specific process of the preparation method is completely same as that of Example 10.

[0095] Comparative Example 10

[0096] A dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: alumina with a particle size of 200-300 nm 31.08%, alumina with a particle size of 25-50 μm 13.32%, zirconium dioxide with a particle size of 50-100 nm 28.575%, zirconium dioxide with a particle size of 50-100 μm 9.525%, silicon dioxide with a particle size of 100-200 nm 12.8%, niobium pentoxide 4.4%, soda ash 0.9%, and manganese dioxide 0.7%.

[0097] The specific process of the preparation method is completely same as that of Example 10.

[0098] Comparative Example 11

[0099] A dense and crack resistant electrically fused zirconia corundum brick, comprising the following raw materials in terms of mass fraction: alumina with particle size of 200-300 nm 31.08%, alumina with particle size of 25-50 μm 13.32%, zirconia with particle size of 50-100 nm 28.575%, zirconia with particle size of 50-100 μm 9.525%, silica with particle size of 100-200 nm 13.5%, niobium pentoxide 4.4%, and soda ash 0.9%;

[0100] The specific process of the preparation method is completely same as that of Example 10.

[0101] Comparative Example 12

[0102] A dense and crack resistant electrically fused zirconia corundum brick, the raw materials and their compositions are completely same as those of Example 5;

[0103] The specific process of the preparation method is partially same as that of Example 5, except that: (3) pouring the above molten liquid with temperature of 2640℃ into a specially designed product mold to form a solid electrically fused brick, and then annealing and cooling, the annealing starting temperature is 2010℃, and the temperature is kept for 2h, and then the temperature is decreased to 450℃ at a rate of 40-50℃ / h, and then the brick is naturally cooled to obtain the dense and crack resistant electrically fused zirconia corundum brick.

[0104] Comparative Example 13

[0105] A dense and crack resistant electrically fused zirconia corundum brick, the raw materials and their compositions are completely same as those of Example 5;

[0106] The specific process of the preparation method is partially same as that of Example 5, except that: (3) pouring the above molten liquid with temperature of 2640℃ into a specially designed product mold to form a solid electrically fused brick, and then annealing and cooling, the annealing starting temperature is 2010℃, and the temperature is kept for 2h, and then the temperature is decreased to 450℃ at a rate of 40-50℃ / h, and then the brick is naturally cooled to obtain the dense and crack resistant electrically fused zirconia corundum brick.

[0107] Comparative Example 14

[0108] A dense and crack resistant electrically fused zirconia corundum brick, the raw materials and their compositions are completely same as those of Example 5;

[0109] The specific process of the preparation method is the same as that in Example 5, except that: (3) the above molten liquid with a pouring temperature of 2640 DEG C is cast in a specially designed product mold to form a solid-state electrically fused brick, which is then annealed and cooled, the annealing starting temperature is 1950 DEG C, the holding time is 2 h, then the temperature is decreased to 450 DEG C at a rate of 70-80 DEG C / h, and then naturally cooled to obtain a dense and crack-resistant electrically fused zirconia corundum brick.

[0110] Performance test of the dense and crack-resistant electrically fused zirconia corundum brick of the test example

[0111] The above Examples 1-12 and Comparative Examples 1-14 are tested according to the Chinese building material industry standard "Fused zirconia corundum refractory products for glass melting furnace" (JC493-2001) and GB / T2997-2015, and the results are shown in Tables 1 and 2.

[0112] Table 1 Test results of Examples 1-12

[0113]

[0114] Table 2 Test results of Examples 1-12

[0115]

[0116]

[0117] A large number of experiments prove that, in combination with Tables 1 and 2 above, the dense and crack-resistant electrically fused zirconia corundum brick of the present application can greatly improve the density and reduce the occurrence of pores of the electrically fused zirconia corundum brick by introducing an appropriate amount of niobium pentoxide into the system composed of an appropriate amount of aluminum oxide, zirconium dioxide and silicon dioxide, and introducing manganese dioxide and copper oxide to synergize with the niobium pentoxide, significantly reducing the diffusion and mutual penetration of the alkaline glass liquid and the precipitated glass phase, and improving the corrosion resistance; at the same time, the density of the electrically fused zirconia corundum brick is greatly improved and the glass phase deformation is significantly reduced by the interaction of the aluminum oxide and the zirconium dioxide in the system through the appropriate particle size ratio; in addition, the present application uses a suitable annealing method to further improve the quality of the dense and crack-resistant electrically fused zirconia corundum brick.

[0118] From Tables 1 and 2, it can be seen that the test results of the examples are better than those of the comparative examples in general; compared with Examples 1-3, in the alumina of Examples 4-7, the mass fraction of the alumina with a particle size of 25-50 μm in the alumina with a particle size of 200-300 nm is 25-30%, and in the zirconia, the mass fraction of the zirconia with a particle size of 50-100 μm in the zirconia with a particle size of 50-100 nm is 20-25%, which makes the properties of the fused zirconia-corundum brick more excellent; furthermore, the component ratio of the component system of Examples 8-10 is more excellent than that of Examples 4-7, and the effect of Example 9 is the best, which is the best example of the present application. The test results of the comparative examples and the examples show that the manganese dioxide, copper oxide and niobium pentoxide, and the alumina with a particle size of 25-50 μm, the alumina with a particle size of 200-300 nm, the zirconia with a particle size of 50-100 μm and the zirconia with a particle size of 50-100 nm provided by the present application are indispensable, and the synergistic effect is obvious, which can promote the uniformity and compactness of the organization layer between the alumina, zirconia and silicon dioxide, greatly reduce the occurrence of pores, significantly improve the compactness of the fused zirconia-corundum brick, further delay the generation and expansion of cracks, improve the high-temperature resistance, corrosion resistance and thermal shock resistance of the fused zirconia-corundum brick, and avoid the fusion.

[0119] In summary, the fused zirconia-corundum brick of the present application has excellent compactness and crack resistance, and can significantly prolong the service life of the refractory material.

[0120] It is apparent for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, but can be implemented in other concrete forms without departing from the spirit and essential characteristics of the present application. Therefore, the examples should be regarded as exemplary and non-limiting in any respect, and the scope of the present application is defined by the appended claims rather than the above description, and all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be encompassed by the present application.

[0121] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the specification is described in this way only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A dense, crack-resistant, electrofused zirconia-alumina brick, characterized in that, The raw materials include, in terms of mass fraction, 42.7-46.6% of alumina, 36.8-40.5% of zirconium dioxide, 11.5-14.2% of silicon dioxide, 2.5-4.4% of niobium pentoxide, 0.7-1.1% of soda ash, 0.6-1% of manganese dioxide and 0.5-1% of copper oxide; The alumina is composed of alumina with a particle size of 200-300 nm and alumina with a particle size of 25-50 μm; The zirconium dioxide is composed of zirconium dioxide with a particle size of 50-100 nm and zirconium dioxide with a particle size of 50-100 μm; The particle size of the silicon dioxide is 100-200 nm; In the alumina, the mass fraction of alumina with a particle size of 25-50 μm in the sum of alumina with a particle size of 25-50 μm and alumina with a particle size of 200-300 nm is 25%, and in the zirconium dioxide, the mass fraction of zirconium dioxide with a particle size of 50-100 μm in the sum of zirconium dioxide with a particle size of 50-100 μm and zirconium dioxide with a particle size of 50-100 nm is 20%; Or, in the alumina, the mass fraction of alumina with a particle size of 25-50 μm in the sum of alumina with a particle size of 25-50 μm and alumina with a particle size of 200-300 nm is 27%, and in the zirconium dioxide, the mass fraction of zirconium dioxide with a particle size of 50-100 μm in the sum of zirconium dioxide with a particle size of 50-100 μm and zirconium dioxide with a particle size of 50-100 nm is 25%; Or, in the alumina, the mass fraction of alumina with a particle size of 25-50 μm in the sum of alumina with a particle size of 25-50 μm and alumina with a particle size of 200-300 nm is 28%, and in the zirconium dioxide, the mass fraction of zirconium dioxide with a particle size of 50-100 μm in the sum of zirconium dioxide with a particle size of 50-100 μm and zirconium dioxide with a particle size of 50-100 nm is 22%; Or, in the alumina, the mass fraction of alumina with a particle size of 25-50 μm in the sum of alumina with a particle size of 25-50 μm and alumina with a particle size of 200-300 nm is 30%, and in the zirconium dioxide, the mass fraction of zirconium dioxide with a particle size of 50-100 μm in the sum of zirconium dioxide with a particle size of 50-100 μm and zirconium dioxide with a particle size of 50-100 nm is 22%; Or, in the alumina, the mass fraction of alumina with a particle size of 25-50 μm in the sum of alumina with a particle size of 25-50 μm and alumina with a particle size of 200-300 nm is 30%, and in the zirconium dioxide, the mass fraction of zirconium dioxide with a particle size of 50-100 μm in the sum of zirconium dioxide with a particle size of 50-100 μm and zirconium dioxide with a particle size of 50-100 nm is 25%.

2. A dense anti-cracking electrically fused zirconia-alumina brick according to claim 1, characterized in that, The dense anti-cracking electrically fused zirconia-corundum brick comprises the following raw materials in terms of mass fraction: 44.4% of alumina, 38.1% of zirconium dioxide, 12.2% of silicon dioxide, 3.1% of niobium pentoxide, 0.9% of soda ash, 0.7% of manganese dioxide and 0.6% of copper oxide.

3. A process for the production of a dense, crack resistant electrofused zirconia-alumina brick according to any one of claims 1 or 2, characterized in that, The method comprises the following steps: (1) Alumina, zirconia and silica are ground to the required particle size, and then mixed with soda ash, niobium pentoxide, manganese dioxide and copper oxide to obtain a mixture; (2) The mixture is poured into an electric arc furnace, melted into a molten liquid at a temperature of 1890-1910 DEG C, and then heated to 2730-2750 DEG C, and then kept warm and subjected to oxygen blowing treatment to remove carbon oxide from the liquid, to obtain a molten liquid; (3) The molten liquid is cast in a specially designed product mold, and annealed and cooled at different cooling rates in stages to obtain dense and crack-resistant electrically fused zirconia corundum bricks.

4. The method of producing a dense anti-cracking electrically fused zirconia-alumina brick according to claim 3, characterized in that, In step (2), the time for keeping warm and oxygen blowing treatment is 20-25 min.

5. The method of producing a dense anti-cracking electrically fused zirconia alumina brick according to claim 3, characterized in that, In step (3), the temperature of the molten liquid during casting is 2600-2650 DEG C.

6. The method of producing a dense anti-cracking electrically fused zirconia-alumina brick according to claim 3, characterized in that, In step (3), the annealing and cooling are carried out at different cooling rates in stages: the initial annealing temperature is 2020-2100 DEG C, first cooled at a rate of 20-30 DEG C / h to 1350-1420 DEG C, then cooled at a rate of 40-50 DEG C / h to 950-1015 DEG C, and then cooled at a rate of 20-30 DEG C / h to 410-460 DEG C, and then naturally cooled.

7. The method of producing a dense anti-cracking electrically fused zirconia alumina brick according to claim 3, characterized in that, When the initial annealing temperature is 2020-2100 DEG C and kept warm for 90-120 min, and when cooled to 1350-1420 DEG C and kept warm for 60-90 min.

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