CN107805059B - Ladle base brick and preparation method thereof - Google Patents
Ladle base brick and preparation method thereof Download PDFInfo
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- CN107805059B CN107805059B CN201711054855.2A CN201711054855A CN107805059B CN 107805059 B CN107805059 B CN 107805059B CN 201711054855 A CN201711054855 A CN 201711054855A CN 107805059 B CN107805059 B CN 107805059B
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/10—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on aluminium oxide
- C04B35/101—Refractories from grain sized mixtures
- C04B35/105—Refractories from grain sized mixtures containing chromium oxide or chrome ore
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
- C04B2235/3206—Magnesium oxides or oxide-forming salts thereof
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
- C04B2235/3222—Aluminates other than alumino-silicates, e.g. spinel (MgAl2O4)
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3418—Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/77—Density
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Compositions Of Oxide Ceramics (AREA)
Abstract
The invention discloses a ladle base brick and a preparation method thereof, wherein the ladle base brick is prepared from a mixture, additional metal aluminum powder and a water reducing agent, wherein the mixture comprises the following raw materials in percentage by weight: 13-22% of tabular corundum particles; 10-20% of alumina particles; 10-30% of chrome corundum particles; 5-20% of spinel particles; 3-10% of magnesia particles; 10-20% of corundum fine powder; 5-10% of alpha-alumina micro powder; 2-6% of silicon micropowder. The ladle base brick disclosed by the invention is suitable for the bottom part of a ladle, and is connected with an upper water gap and a lower water gap and a sliding plate, the service life of the bottom part of the ladle can be effectively prolonged by using the product, and meanwhile, the product contains the chromium corundum waste, so that the waste is fully utilized, the technical index requirements can be met, and the ladle base brick has remarkable social benefit and economic benefit. The production cost per ton can be saved by 250-300 Yuan compared with the original production cost.
Description
Technical Field
The invention belongs to the field of refractory material unshaped products, and particularly relates to a ladle base brick and a preparation method thereof.
Background
At present, the steel ladle base brick mainly adopts corundum spinel or corundum, and because the corundum spinel brick contains more plate-shaped corundum or white corundum, spinel and other stable-performance materials, the performance of the corundum spinel brick is very stable, but the production and manufacturing cost of the corundum spinel brick is also improved along with the continuous rising of the price of corundum raw materials. How to save the production and manufacturing cost while ensuring the stable performance of the ladle base brick is a common problem in the steel production industry at present.
Disclosure of Invention
In order to solve the problems, the invention provides a ladle bottom brick and a preparation method thereof, wherein chromium corundum particles are added into raw materials, the chromium corundum is mainly electric smelting chromium corundum, which is a waste generated in the process of preparing metal chromium or chromium alloy by external smelting, the technical index of the ladle bottom brick produced by using the chromium corundum is equivalent to that of the existing corundum cementing material, the use requirement of a steel mill can be met, and the production cost is obviously reduced.
The technical scheme adopted by the invention is as follows:
the ladle base brick is prepared from a mixture, additional metal aluminum powder and a water reducing agent, wherein the mixture comprises the following raw materials in percentage by weight:
further, the mixture preferably comprises the following raw materials in percentage by weight:
the weight of the metal aluminum powder is 0.1-1% of the weight of the mixture.
The weight of the water reducing agent is 0.1-1% of the weight of the mixture.
The water reducing agent comprises one or more of an ADS type high-efficiency water reducing agent, an ADW type high-efficiency water reducing agent or an FS10 high-efficiency water reducing agent.
The corundum fine powder is white corundum fine powder, and Al in the components2O3The content is more than or equal to 98.5 percent, and the pH value of the white corundum fine powder is neutral.
The spinel particles are magnesia-alumina spinel particles, and the content of MgO in the components is more than or equal to 34 percent, and MgO + Al2O3-The content is more than or equal to 90 percent.
Al in the composition of the alumina particles2O3More than or equal to 88 percent; the MgO content in the components of the fused magnesia particles is more than or equal to 97 percent, and the SiO content in the components of the silicon micro powder2The content is more than or equal to 90 percent.
The content of alumina in the components of the chromium corundum particles is more than 94 percent, and the content of chromium oxide is less than 3 percent.
The invention also provides a preparation method of the ladle bottom brick, which comprises the following steps:
(1) premixing corundum fine powder, alpha-alumina micro powder, silica micro powder, metal aluminum powder and a water reducing agent for 25-30 min to obtain premixed fine powder;
(2) adding tabular corundum particles, alumina particles, chrome corundum particles, spinel particles and magnesia particles into a mixing roll according to the formula ratio, mixing and grinding for 1-2 minutes, adding the premixed fine powder obtained in the step (1), continuing mixing and grinding for 2-3 minutes, and adding water until the surface of the mud is slurried, wherein the total mixing and grinding time is 8-12 minutes;
(3) pouring, vibrating, forming, demolding and baking;
(4) and (6) inspecting and packaging.
Further, the baking temperature is 350-400 ℃, and the baking time is 36-48 h.
In the formula of the ladle base brick provided by the invention, the alumina particles and the tabular corundum particles provide a skeleton supporting effect, so that the strength, the erosion resistance and other properties of the product can be improved, the spinel particles are smaller, the filling compensation effect is achieved, the molten steel erosion resistance of the product can be improved at high temperature, and the high-temperature sintering property of the product can be improved by the micropowder and the water reducing agent. The chromium corundum particles are used as a solid solution of aluminum oxide and chromium oxide, and can effectively connect particles and fine powder in the components, so that the strength of the product is greatly improved. In the formula, the arrangement of different grain size grades of the raw materials accords with the tight packing principle, and the strength of the product is favorably improved. The high-efficiency water reducing agent is different from common trimerization and hexametaphosphate water reducing agents, can greatly reduce the water adding amount, eliminates the adverse effect on the product performance caused by air holes left after water volatilization, and can obviously improve the normal temperature strength index of the product.
The ladle base brick disclosed by the invention is suitable for the bottom part of a ladle, and is connected with an upper water gap and a lower water gap and a sliding plate, the service life of the bottom part of the ladle can be effectively prolonged by using the product, and meanwhile, because the product contains chromium corundum (aluminum chromium slag) waste, the waste is fully utilized and can meet the technical index requirements, and the compressive strength of the ladle base brick obtained by using the method disclosed by the invention is more than or equal to 60Mpa, and the body density is more than or equal to 3g/cm3The breaking strength is more than or equal to 8Mpa, and the refractoriness under load is more than or equal to 1500 ℃; has remarkable social and economic benefits. The production cost per ton can be saved by 250-300 Yuan compared with the original production cost.
Detailed Description
Example 1
A ladle base brick is prepared from a mixture, additional metal aluminum powder and an ADS type high-efficiency water reducing agent, wherein the mixture comprises the raw materials in percentage by weight shown in Table 1, the metal aluminum powder and the ADS type high-efficiency water reducing agent are respectively 0.5% and 1.0% of the mixture, and the particle size of the metal aluminum powder is 325 meshes.
The preparation method of the ladle base brick comprises the following steps:
(1) premixing corundum fine powder, alpha-alumina micro powder, silica micro powder, metal aluminum powder and a water reducing agent for 25-30 min to obtain premixed fine powder;
(2) adding tabular corundum particles, alumina particles, chrome corundum particles, spinel particles and magnesia particles into a mixing roll according to the formula ratio, mixing and grinding for 1-2 minutes, adding the premixed fine powder obtained in the step (1), continuing mixing and grinding for 2-3 minutes, and adding water until the surface of the mud is slurried, wherein the total mixing and grinding time is 8-12 minutes;
(3) pouring, vibrating, molding, demolding, and baking at 350-400 ℃ for 36-48 h;
(4) and (6) inspecting and packaging.
TABLE 1
Example 2
The ladle base brick is prepared from a mixture, additional metal aluminum powder and an ADW type high-efficiency water reducing agent, wherein the mixture comprises the raw materials in percentage by weight shown in table 1, the weight of the metal aluminum powder and the weight of the water reducing agent are respectively 0.7% and 0.8% of the weight of the mixture, and the particle size of the metal aluminum powder is 325 meshes.
The preparation method of the ladle base brick comprises the following steps:
(1) premixing fine corundum powder, alpha-alumina micro powder, silica micro powder, metal aluminum powder and ADW type high-efficiency water reducing agent for 25-30 min to obtain premixed fine powder;
(2) adding tabular corundum particles, alumina particles, chrome corundum particles, spinel particles and magnesia particles into a mixing roll according to the formula ratio, mixing and grinding for 1-2 minutes, adding the premixed fine powder obtained in the step (1), continuing mixing and grinding for 2-3 minutes, and adding water until the surface of the mud is slurried, wherein the total mixing and grinding time is 8-12 minutes;
(3) pouring, vibrating, molding, demolding, and baking at 350-400 ℃ for 36-48 h;
(4) and (6) inspecting and packaging.
TABLE 2
Comparative example 1
The rest is the same as the example 1 except that the ADS type high efficiency water reducing agent is replaced by the melamine water reducing agent.
Comparative example 2
The procedure is otherwise the same as in example 1, except that the particle diameters of all the granulated starting materials are replaced by 5 to 3 mm.
Comparative example 3
The procedure is otherwise the same as in example 1, except that 15% of the corundum particles of chromium are replaced with 15% of corundum particles of tabular corundum and 10% of fused magnesia.
The results of the performance tests of the ladle floor tiles obtained in the above examples and comparative examples are shown in table 3.
TABLE 3 Performance test results of ladle base bricks obtained in examples and comparative examples
The above detailed description of a ladle seating brick and a method for manufacturing the same with reference to the embodiments is illustrative and not restrictive, and several embodiments can be cited within the scope of the present invention, so that changes and modifications that do not depart from the general concept of the present invention are intended to be included within the scope of the present invention.
Claims (6)
1. The ladle base brick is characterized by being prepared from a mixture, additional metal aluminum powder and a water reducing agent, wherein the mixture is prepared from the following raw materials in percentage by weight:
8-12% of plate-shaped corundum particles with the particle size of 8-5 mm;
5-10% of plate-shaped corundum particles with the particle size of 3-1 mm;
10-20% of 5-3mm alumina particles;
5-15% of chrome corundum particles with the particle size of 3-1 mm;
5-15% of chrome corundum particles with the particle size of 1-0 mm;
1-0mm spinel particles 5-20%;
3-10% of 1-0mm magnesite grains;
10-20% of 100-plus 180-mesh corundum fine powder;
5-10% of alpha-alumina micro powder;
2-6% of silicon micropowder;
the weight of the metal aluminum powder is 0.1-1% of the weight of the mixture;
the weight of the water reducing agent is 0.1-1% of the weight of the mixture.
2. The ladle base brick according to claim 1, wherein the water reducer comprises one or more of an ADS type high efficiency water reducer, an ADW type high efficiency water reducer, or an FS10 high efficiency water reducer.
3. The ladle base brick according to claim 1, wherein the corundum-based fine powder is white corundum fine powder, and the composition of the corundum-based fine powder is Al2O3The content is more than or equal to 98.5 percent, and the pH value of the white corundum fine powder is neutral.
4. The ladle base brick as recited in claim 1, wherein the spinel particles are magnesia alumina spinel particles having a MgO content of 34% or more and MgO + Al2O3The content is more than or equal to 90 percent.
5. A method of making a ladle floor tile according to claim 1, comprising the steps of:
(1) premixing corundum fine powder, alpha-alumina micro powder, silica micro powder, metal aluminum powder and a water reducing agent for 25-30 min to obtain premixed fine powder;
(2) adding tabular corundum particles, alumina particles, chrome corundum particles, spinel particles and magnesia particles into a mixing roll according to the formula ratio, mixing and grinding for 1-2 minutes, adding the premixed fine powder obtained in the step (1), continuing mixing and grinding for 2-3 minutes, and adding water until the surface of the mud is slurried, wherein the total mixing and grinding time is 8-12 minutes;
(3) pouring, vibrating, forming, demolding and baking;
(4) and (6) inspecting and packaging.
6. The preparation method of claim 5, wherein the baking temperature is 350-400 ℃ and the baking time is 36-48 h.
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| CN201711054855.2A CN107805059B (en) | 2017-11-01 | 2017-11-01 | Ladle base brick and preparation method thereof |
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| CN201711054855.2A CN107805059B (en) | 2017-11-01 | 2017-11-01 | Ladle base brick and preparation method thereof |
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| CN107805059B true CN107805059B (en) | 2020-09-25 |
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Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110272268A (en) * | 2018-03-17 | 2019-09-24 | 鞍山盛晨耐火材料有限公司 | A kind of preparation method of ladle corundum lining brick |
| CN109180165B (en) * | 2018-08-26 | 2022-02-22 | 洛阳科创新材料股份有限公司 | Preparation method of sliding plate brick |
| CN109987952A (en) * | 2019-04-25 | 2019-07-09 | 郑州振东科技有限公司 | Spinel ladle heat insulation lining brick |
| CN110776312A (en) * | 2019-09-30 | 2020-02-11 | 山东耀华特耐科技有限公司 | Cement-free castable |
| CN110981513A (en) * | 2019-12-30 | 2020-04-10 | 马鞍山利尔开元新材料有限公司 | Chrome corundum slag-high bauxite composite carbon-free ladle down nozzle brick and preparation method thereof |
| CN112299824A (en) * | 2020-11-25 | 2021-02-02 | 安徽省萧县华龙耐火材料有限责任公司 | Cement-free ladle nozzle pocket brick |
| CN114085071A (en) * | 2021-12-15 | 2022-02-25 | 无锡远能耐火材料有限公司 | High-chromium corundum refractory brick for high-temperature plasma melting furnace lining and preparation method thereof |
| CN114538940B (en) * | 2022-01-27 | 2023-03-03 | 北京利尔高温材料股份有限公司 | Tundish pocket brick cup containing reclaimed materials and preparation method thereof |
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| JPH04119962A (en) * | 1990-09-06 | 1992-04-21 | Harima Ceramic Co Ltd | Magnesia-carbon refractories |
| CN102173826A (en) * | 2010-12-30 | 2011-09-07 | 中南大学 | Corundum breathable seat brick with high thermal shock resistance and production method thereof |
| CN106631050B (en) * | 2015-11-05 | 2019-12-10 | 洛阳轩石新材料科技有限公司 | Cleaning-free air brick with uniform structure and manufacturing method thereof |
| CN105272311A (en) * | 2015-11-11 | 2016-01-27 | 浙江长兴宝晟炉料有限公司 | Low-cost durable main ditch material |
| CN106631068A (en) * | 2016-12-27 | 2017-05-10 | 通达耐火技术股份有限公司 | Bauxite-based homogenous corundum environment-friendly steel ladle base brick and preparation method |
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Effective date of registration: 20180413 Address after: 243000 53 intelligent equipment Industrial Park in Yushan Economic Development Zone, Ma'anshan, Anhui Applicant after: Ruitai Magang new Mstar Technology Ltd Applicant after: Magang (Group) Holding Company Ltd. Address before: 243000 Anhui city in Ma'anshan Province, Huashan District Tianmen Middle Road No. 2256 Applicant before: ANHUI MA STEEL REFRACTORY CO., LTD. |
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