CN117756507A - High-temperature thermal shock resistant high-purity corundum brick and preparation method thereof - Google Patents
High-temperature thermal shock resistant high-purity corundum brick and preparation method thereof Download PDFInfo
- Publication number
- CN117756507A CN117756507A CN202311851808.6A CN202311851808A CN117756507A CN 117756507 A CN117756507 A CN 117756507A CN 202311851808 A CN202311851808 A CN 202311851808A CN 117756507 A CN117756507 A CN 117756507A
- Authority
- CN
- China
- Prior art keywords
- alpha
- corundum
- powder
- particles
- parts
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000010431 corundum Substances 0.000 title claims abstract description 84
- 229910052593 corundum Inorganic materials 0.000 title claims abstract description 84
- 239000011449 brick Substances 0.000 title claims abstract description 48
- 230000035939 shock Effects 0.000 title claims abstract description 21
- 238000002360 preparation method Methods 0.000 title abstract description 17
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims abstract description 55
- 239000002245 particle Substances 0.000 claims abstract description 47
- 239000000843 powder Substances 0.000 claims abstract description 41
- 238000005245 sintering Methods 0.000 claims abstract description 34
- 239000011858 nanopowder Substances 0.000 claims abstract description 28
- 159000000003 magnesium salts Chemical class 0.000 claims abstract description 16
- 239000002270 dispersing agent Substances 0.000 claims abstract description 13
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000000853 adhesive Substances 0.000 claims abstract description 10
- 230000001070 adhesive effect Effects 0.000 claims abstract description 10
- 239000002994 raw material Substances 0.000 claims abstract description 10
- 239000002002 slurry Substances 0.000 claims description 14
- YIXJRHPUWRPCBB-UHFFFAOYSA-N magnesium nitrate Chemical compound [Mg+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O YIXJRHPUWRPCBB-UHFFFAOYSA-N 0.000 claims description 12
- 239000011159 matrix material Substances 0.000 claims description 12
- 238000001694 spray drying Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 238000000498 ball milling Methods 0.000 claims description 11
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 239000000725 suspension Substances 0.000 claims description 9
- 238000002156 mixing Methods 0.000 claims description 8
- 239000007787 solid Substances 0.000 claims description 8
- 239000007864 aqueous solution Substances 0.000 claims description 7
- 239000000203 mixture Substances 0.000 claims description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 6
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims description 5
- 235000019341 magnesium sulphate Nutrition 0.000 claims description 5
- 229920002472 Starch Polymers 0.000 claims description 4
- 239000011230 binding agent Substances 0.000 claims description 4
- 235000019698 starch Nutrition 0.000 claims description 4
- 239000008107 starch Substances 0.000 claims description 4
- YWYZEGXAUVWDED-UHFFFAOYSA-N triammonium citrate Chemical compound [NH4+].[NH4+].[NH4+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O YWYZEGXAUVWDED-UHFFFAOYSA-N 0.000 claims description 4
- VXAUWWUXCIMFIM-UHFFFAOYSA-M aluminum;oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Al+3] VXAUWWUXCIMFIM-UHFFFAOYSA-M 0.000 claims description 3
- 238000000748 compression moulding Methods 0.000 claims description 2
- 238000001125 extrusion Methods 0.000 claims description 2
- 238000000462 isostatic pressing Methods 0.000 claims description 2
- 238000000465 moulding Methods 0.000 claims description 2
- 239000011819 refractory material Substances 0.000 abstract description 4
- 239000012752 auxiliary agent Substances 0.000 abstract description 2
- 238000013461 design Methods 0.000 abstract description 2
- 230000000052 comparative effect Effects 0.000 description 19
- 238000012360 testing method Methods 0.000 description 7
- 239000000654 additive Substances 0.000 description 4
- ALSTYHKOOCGGFT-KTKRTIGZSA-N (9Z)-octadecen-1-ol Chemical compound CCCCCCCC\C=C/CCCCCCCCO ALSTYHKOOCGGFT-KTKRTIGZSA-N 0.000 description 3
- 230000000996 additive effect Effects 0.000 description 3
- 238000005266 casting Methods 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000005469 granulation Methods 0.000 description 3
- 230000003179 granulation Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 229940055577 oleyl alcohol Drugs 0.000 description 3
- XMLQWXUVTXCDDL-UHFFFAOYSA-N oleyl alcohol Natural products CCCCCCC=CCCCCCCCCCCO XMLQWXUVTXCDDL-UHFFFAOYSA-N 0.000 description 3
- 235000011837 pasties Nutrition 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- 238000003825 pressing Methods 0.000 description 3
- 238000001878 scanning electron micrograph Methods 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 238000010998 test method Methods 0.000 description 3
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 239000012798 spherical particle Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- -1 and meanwhile Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000007580 dry-mixing Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007676 flexural strength test Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- KKCBUQHMOMHUOY-UHFFFAOYSA-N sodium oxide Chemical compound [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 1
- 229910001948 sodium oxide Inorganic materials 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
Abstract
The invention relates to the technical field of corundum refractory materials, and discloses a high-temperature thermal shock resistant high-purity corundum brick and a preparation method thereof, wherein the high-purity corundum brick is single alpha-Al 2 O 3 The phase comprises the following raw material components in parts by weight: 55-65 parts of corundum particles, 25-36 parts of corundum fine powder and alpha-Al 2 O 3 4-12 parts of micro powder, alpha-Al 2 O 3 0.5-3 parts of nano powder, a soluble inorganic magnesium salt sintering aid, an adhesive and a dispersing agent. The invention reduces the sintering temperature by the grading design of the alumina powder and the selection of the sintering auxiliary agent, and the obtained product is single alpha-Al 2 O 3 The phase has excellent high temperature and thermal shock resistanceCan be used in the working environment with the temperature of more than 1800 ℃.
Description
Technical Field
The invention relates to the technical field of corundum refractory materials, in particular to a high-purity corundum brick resistant to high-temperature thermal shock and a preparation method thereof.
Background
The high-purity corundum brick is a high-quality refractory product and is mainly used for important high-temperature parts of chemical and metallurgical kilns. The research on the high-purity alumina furnace bricks for the sintering furnace in China is less in the high-purity application scene, raw materials such as alumina and the like are mainly cast into alumina casting bricks after electric melting in China, and in order to reduce the melting temperature and shrinkage after casting, sintering aids such as alumina nano powder, sodium oxide or silicon oxide and the like are often introduced into the raw materials, so that the high-temperature resistance of the alumina casting materials is difficult to meet the application requirements above 1700 ℃.
Chinese patent CN105237003a reduces alpha-Al by adding titanium dioxide micropowder, stone micropowder to the raw material 2 O 3 The amount of nano powder is small, but the mechanical property of the prepared high-purity corundum brick is poor in a high-temperature environment with the temperature of 1700 ℃ or higher.
Therefore, there is a need to develop a high purity corundum brick which can be used in high temperature environments above 1800 ℃.
Disclosure of Invention
Based on the technical problems in the prior art, the invention provides a high-purity corundum brick resistant to high-temperature thermal shock and a preparation method thereof. The alumina furnace brick with low density, heat conductivity, micropore structure, high strength, high thermal shock resistance and heat preservation is prepared by optimizing the gradation of the grain size of the alumina raw material and the preparation method.
In order to achieve the above object, the technical scheme of the present invention is as follows:
a high-temperature thermal shock resistant high-purity corundum brick, which is a single alpha-Al 2 O 3 The phase comprises the following raw material components in parts by weight: 55-65 parts of corundum particles, 25-36 parts of corundum fine powder and alpha-Al 2 O 3 4-12 parts of micro powder, alpha-Al 2 O 3 0.5-3 parts of nano powder, a soluble inorganic magnesium salt sintering aid, an adhesive and a dispersing agent;
wherein the usage amount (calculated by MgO content) of the soluble inorganic magnesium salt sintering aid is corundum particles, corundum fine powder and alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 0.15-0.25% of the total amount of the nano powder;
the dosage of the adhesive is alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 5-10% of the total consumption of the nano powder;
the dosage of the dispersing agent is alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 0.25-2.5% of the total consumption of the nano powder.
Preferably, the corundum particles are of particle size=1-3 mm, al 2 O 3 Fused corundum particles with the content of more than or equal to 99.5 percent; the corundum fine powder has a particle size of=0.01-0.05 mm and Al 2 O 3 Fine powder of fused corundum with the content more than or equal to 99.5 percent; the alpha-Al 2 O 3 The micro powder has a particle size d50=1-4 μm and Al 2 O 3 alpha-Al with content more than or equal to 99.6% 2 O 3 Micropowder of alpha-Al 2 O 3 The nanometer powder has average particle diameter of 30-50nm and Al 2 O 3 alpha-Al with content more than or equal to 99.9% 2 O 3 A nano powder.
Preferably, the alpha-Al 2 O 3 The specific surface area of the nano powder is (80+/-5) m 2 /g。
Preferably, the binder is any one or a mixture of more of PVA, starch or pseudo-boehmite sol binders.
Preferably, the soluble inorganic magnesium salt sintering aid is any one or a mixture of two of magnesium nitrate and magnesium sulfate.
In the application, the soluble inorganic magnesium salt additive is added in the form of aqueous solution, and the addition in the form of liquid phase is convenient for dispersing the additive and is beneficial to sintering. Magnesium salt additives are in fact decomposed into MgO during sintering, so magnesium nitrate or magnesium sulfate, which is decomposed into MgO during sintering, is chosen as additive in the present application, the amount being calculated as MgO content.
Preferably, the dispersing agent comprises any one of ammonium citrate and hydrochloric acid.
The invention also provides a preparation method of the high-purity corundum brick, which comprises the following steps:
s1, alpha-Al 2 O 3 Micro powder, alpha-Al 2 O 3 Mixing the nano powder suspension, a dispersing agent, a soluble inorganic magnesium salt sintering aid aqueous solution, an adhesive and water, and ball milling to prepare a matrix green compact slurry;
s2, spray drying the matrix green compact slurry prepared in the step S1 to obtain spherical alpha-Al with the particle size of 50-100 mu m 2 O 3 Particles;
s3, spherical alpha-Al obtained in the step S2 is prepared 2 O 3 The particles, corundum particles and corundum fine powder are uniformly mixed, pressed, formed and dried and sintered at 1300-1700 ℃ to obtain the high-purity corundum brick.
Preferably, in step S1, the solid content of alumina in the slurry is 35-45%. More preferably, the solids content of alumina in the slurry is 40%.
Preferably, in step S1, the α -Al 2 O 3 The nano powder suspension is alpha-Al 2 O 3 Suspension of nano-powder dissolved in water. The amount of water used is not limited as long as a suspension and alpha-Al can be formed 2 O 3 The micro powder is fully and uniformly mixed.
Preferably, in step S2, the spray-drying temperature is 160-200 ℃. More preferably, the spray drying temperature is 180 ℃.
Preferably, in step S3, the sintering time is 4-6 hours; preferably, the sintering temperature is 1400-1500 ℃.
Preferably, in step S3, the pressing mode is any one of compression molding, extrusion molding or isostatic pressing.
In the invention, corundum particles and corundum fine powder are used as furnace brick aggregate and are matched with alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 The nano powder is used as a matrix to obtain a uniform furnace brick structure, so that the high strength of the furnace brick is ensured; at the same time alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 The introduction of the nano powder can increase the sintering performance and reduce the sintering temperature; hollow spherical alpha-Al obtained by spray granulation 2 O 3 The microporous structure of the particles increases the thermal shock resistance and the heat preservation of the corundum bricks, and reduces the weight.
Compared with the prior art, the invention has the following beneficial effects:
the high-temperature thermal shock resistant high-purity corundum brick of the invention is a single alpha-Al 2 O 3 The phase has good high temperature resistance, thermal shock resistance and high temperature strength, high manufacturing precision, safe and reliable use and long service life.
According to the method, the sintering temperature of the high-purity corundum is greatly reduced by combining the granularity grading with the sintering auxiliary agent, and meanwhile, spherical particles are prepared by spray granulation, so that the porosity of the material is improved. And the molding is simple and convenient, the product strength is higher, and meanwhile, the ceramic powder and the pore-forming agent can be well mixed, so that the pore-size structure is more uniformly distributed.
Drawings
FIG. 1 is an XRD pattern of the high purity corundum brick prepared in example 1.
FIG. 2 is an SEM image of a high purity corundum brick prepared in example 2.
FIG. 3 is an SEM image of a high purity corundum brick prepared in comparative example 6.
Figure 4 is an SEM image of the product after calcination at different spray drying inlet temperatures,
wherein, (a) 120 ℃, (b) 140 ℃, (c) 160 ℃, (d) 180 ℃, (e) 200 ℃.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The invention may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit or scope of the invention, which is therefore not limited to the specific embodiments disclosed below.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
In the present invention, corundum particles are of particle size=1 to 3mm, al 2 O 3 Fused corundum particles with the content of more than or equal to 99.5 percent; the corundum fine powder has particle diameter of 0.01-0.05mm and Al 2 O 3 Fine powder of fused corundum with the content more than or equal to 99.5 percent; alpha-Al 2 O 3 The micro powder has a particle size d50=1-4 μm and Al 2 O 3 alpha-Al with content more than or equal to 99.6% 2 O 3 Micro powder, alpha-Al 2 O 3 The nanometer powder has average particle diameter of 30-50nm and Al 2 O 3 alpha-Al with content more than or equal to 99.9% 2 O 3 A nano powder. The other raw materials are common commercial products unless specified.
The amounts of the raw materials used in examples 1 to 3 and comparative examples 1 to 3 are shown in Table 1.
TABLE 1 raw material amounts for examples 1-3 and comparative examples 1-3
Example 1
A preparation method of a high-temperature thermal shock resistant high-purity corundum brick comprises the following steps:
s1. Alpha. -Al was used in the amount of example 1 in Table 1 2 O 3 Micro powder, alpha-Al 2 O 3 Suspension of nano-powder (alpha-Al) 2 O 3 Mixing nano powder with a proper amount of water), a dispersing agent (ammonium citrate), a soluble inorganic magnesium salt sintering aid aqueous solution (magnesium sulfate solution), an adhesive (a mixture of PVA and pseudo-boehmite) and a proper amount of water, heating to be pasty at 90 ℃, pouring into a ball milling tank after cooling, and ball milling for 12 hours after 2 drops of oleyl alcohol are dripped into the ball milling tank to obtain a matrix green body slurry with the solid content of 40%;
s2, spray drying the matrix green compact slurry prepared in the step S1 at 180 ℃ to obtain spherical alpha-Al with the particle size of 50-100 mu m 2 O 3 Particles;
s3, spherical alpha-Al obtained in the step S2 is prepared 2 O 3 Uniformly mixing the particles, corundum particles and corundum fine powder, isostatic compaction, drying and sintering for 5 hours at 1400 ℃ to obtain the high-purity corundum brick.
Example 2
A preparation method of a high-temperature thermal shock resistant high-purity corundum brick comprises the following steps:
s1. Alpha. -Al was used in the amount of example 2 in Table 1 2 O 3 Micro powder, alpha-Al 2 O 3 Suspension of nano-powder (alpha-Al) 2 O 2 Mixing the nano powder with a proper amount of water), a dispersing agent (ammonium citrate), a soluble inorganic magnesium salt sintering aid aqueous solution (magnesium nitrate solution), an adhesive (a mixture of starch and PVA) and a proper amount of water, heating to be pasty at 90 ℃, pouring into a ball milling tank after cooling, and ball milling for 12 hours after 2 drops of oleyl alcohol are dripped into the ball milling tank to obtain a matrix green body slurry with the solid content of 40%;
s2, spray drying the matrix green compact slurry prepared in the step S1 at 200 ℃ to obtain spherical alpha-Al with the particle size of 50-100 mu m 2 O 3 Particles;
s3, spherical alpha-Al obtained in the step S2 is prepared 2 O 3 The particles, corundum particles and corundum fine powder are uniformly mixed, molded, dried and sintered for 6 hours at 1500 ℃ to obtain the high-purity corundum brick.
Example 3
A preparation method of a high-temperature thermal shock resistant high-purity corundum brick comprises the following steps:
s1. Alpha. -Al was used in the amount of example 3 in Table 1 2 O 3 Micro powder, alpha-Al 2 O 3 Suspension of nano-powder (alpha-Al) 2 O 3 Mixing the nano powder with a proper amount of water), a dispersing agent (hydrochloric acid), a soluble inorganic magnesium salt sintering aid aqueous solution (magnesium sulfate solution), an adhesive (a mixture of starch and PVA) and a proper amount of water, heating to be pasty at 90 ℃, pouring into a ball milling tank after cooling, and ball milling for 12 hours after 2 drops of oleyl alcohol are dripped into the ball milling tank to obtain a matrix green body slurry with the solid content of 35%;
s2, spray drying the matrix green compact slurry prepared in the step S1 at 160 ℃ to obtain spherical alpha-Al with the particle size of 50-100 mu m 2 O 3 Particles;
s3, spherical alpha-Al obtained in the step S2 is prepared 2 O 3 The particles, corundum particles and corundum fine powder are uniformly mixed, extruded, formed and baked for 4 hours at 1700 ℃ to obtain the high-purity corundum brick.
Comparative example 1
According to the amounts of the components of comparative example 1 in Table 1, high purity corundum bricks were prepared by the preparation method of example 2.
Comparative example 2
According to the amounts of the components of comparative example 2 in table 1, high purity corundum bricks were prepared with reference to the preparation method of example 2.
Comparative example 3
According to the amounts of the components of comparative example 3 in table 1, high purity corundum bricks were prepared by the preparation method of example 2.
Comparative example 4
According to the amounts of the components of example 2 in table 1, high purity corundum bricks were prepared with reference to the preparation method of example 2.
Wherein, the soluble magnesium salt sintering aid magnesium nitrate is added in a solid form.
Comparative example 5
According to the amounts of the components of example 2 in table 1, high purity corundum bricks were prepared with reference to the preparation method of reference example 2.
Wherein, the amount of the soluble inorganic magnesium salt sintering aid (calculated by MgO) is 0.3g.
Comparative example 6
The preparation method according to the component amounts of example 2 in table 1 is: corundum particles, corundum fine powder and alpha-Al 2 O 3 After dry mixing the micro powder, adding proper amount of deionized water alpha-Al 2 O 3 Mixing the nano powder suspension, magnesium nitrate aqueous solution and a dispersing agent, and pressing the obtained powder; sintering at 1400 deg.c for 5 hr.
Performance testing
1. XRD analysis was performed on the high purity corundum brick obtained in example 1, as shown in FIG. 1, which is a single alpha-Al 2 O 3 And (3) phase (C).
2. SEM tests were carried out on the high purity corundum bricks obtained in example 2 and comparative example 6. As shown in FIGS. 2 to 3, the high purity corundum bricks obtained in comparative example 6, which were not subjected to spray drying granulation, were more dense, small in voids, and had uneven surfaces and more defects.
The green matrix slurry prepared in example 2 was spray-dried and granulated at an inlet temperature of 120℃at 140℃at 160℃at 180℃at 200℃respectively, and the results are shown in FIG. 4, and it can be seen that hollow alpha-Al was obtained at an inlet temperature of 160 to 200℃and particularly at 180 ℃ 2 O 3 The spherical particles are more regular and have uniform air holes.
3. Mechanical property test
The high purity corundum bricks prepared in examples 1 to 3 and comparative examples 1 to 6 were tested for compressive strength, compressive strength after 10 times of thermal shock, density and normal temperature flexural strength. The test method is as follows:
density test execution criteria: and measuring the density and the relative density of GB/T4472-2011 chemical products.
Porosity test execution standard: GB/T2997-2015 compact shaped refractory product volume density, apparent porosity and true porosity test method.
Normal temperature flexural strength: GB/T3001-2017 refractory material normal temperature flexural strength test method.
Normal temperature compressive strength: GB/T5072-2008 refractory material normal temperature compressive strength test method.
The method for testing the thermal shock resistance comprises the following steps: placing the sample into a resistance furnace, preserving heat at 1800 ℃ for 20min, taking out, placing into cold water for quenching, placing into air for 20min, placing into the furnace for preserving heat for 20min, and repeating the steps for ten times. The compressive strength was tested.
The test results are shown in Table 2.
TABLE 2
Analysis is carried out in combination with tables 1 and 2, the difference between the example 2 and the comparative examples 1-3 is the variation of the corundum powder grading, the compressive strength and the high-temperature thermal shock resistance of the high-purity corundum bricks obtained in the example 2 are obviously better than those of the comparative examples 1-3, and unexpected technical effects are obtained by the grading design in the application. By comparing the examples with comparative examples 4 to 5, when the sintering aid is added in the form of a solid, the compressive strength is lowered and the thermal shock resistance is drastically lowered, and when the sintering aid is excessive, the compressive strength and the thermal shock resistance are remarkably lowered. As is evident from a comparison of examples and comparative example 6, alpha-Al is reduced 2 O 3 The preparation method of spray drying and granulating the micro powder and then mixing with corundum particles and corundum fine powder, pressing and sintering is superior to the method without spray drying, and the obtained high-purity corundum brick product has higher porosity, lower density and better high-temperature shock resistance.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.
Claims (10)
1. A high-temperature thermal shock resistant high-purity corundum brick is characterized in that the high-purity corundum brick is a single alpha-Al 2 O 3 The phase comprises the following raw material components in parts by weight: 55-65 parts of corundum particles, 25-36 parts of corundum fine powder and alpha-Al 2 O 3 4-12 parts of micro powder, alpha-Al 2 O 3 0.5-3 parts of nano powder, a soluble inorganic magnesium salt sintering aid, an adhesive and a dispersing agent;
wherein the usage amount (calculated by MgO content) of the soluble inorganic magnesium salt sintering aid is corundum particles, corundum fine powder and alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 0.15-0.25% of the total amount of the nano powder;
the dosage of the adhesive is alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 5-10% of the total consumption of the nano powder;
the dosage of the dispersing agent is alpha-Al 2 O 3 Micropowder and alpha-Al 2 O 3 0.25-2.5% of the total consumption of the nano powder.
2. A high purity corundum brick according to claim 1 characterized in that the corundum particles are of particle size = 1-3mm, al 2 O 3 Fused corundum particles with the content of more than or equal to 99.5 percent; the corundum fine powder has a particle size of=0.01-0.05 mm and Al 2 O 3 Fine powder of fused corundum with the content more than or equal to 99.5 percent; the alpha-Al 2 O 3 The micro powder has a particle size d50=1-4 μm and Al 2 O 3 alpha-Al with content more than or equal to 99.6% 2 O 3 Micropowder of alpha-Al 2 O 3 The nanometer powder has average particle diameter of 30-50nm and Al 2 O 3 alpha-Al with content more than or equal to 99.9% 2 O 3 A nano powder.
3. A high purity corundum brick according to claim 1 characterized in that the binder is any one or a mixture of more of PVA, starch or pseudo-boehmite sol binder.
4. A high purity corundum brick according to claim 1 characterized in that the soluble inorganic magnesium salt sintering aid is any one or a mixture of two of magnesium nitrate and magnesium sulfate.
5. A high purity corundum brick according to claim 1 characterized in that the dispersant comprises any one of ammonium citrate, hydrochloric acid.
6. A method for preparing a high purity corundum brick as claimed in any one of claims 1-5 comprising the steps of:
s1, alpha-Al 2 O 3 Micro powder, alpha-Al 2 O 3 Mixing the nano powder suspension, a dispersing agent, a soluble inorganic magnesium salt sintering aid aqueous solution, an adhesive and water, and ball milling to prepare a matrix green compact slurry;
s2, spray drying the matrix green compact slurry prepared in the step S1 to obtain spherical alpha-Al with the particle size of 50-100 mu m 2 O 3 Particles;
s3, spherical alpha-Al obtained in the step S2 is prepared 2 O 3 The particles, corundum particles and corundum fine powder are uniformly mixed, pressed, formed and dried and sintered at 1300-1700 ℃ to obtain the high-purity corundum brick.
7. The method according to claim 6, wherein in step S1, the solid content of alumina in the slurry is 35-45%.
8. The method according to claim 6, wherein in step S2, the spray-drying is performed at a temperature of 160-200 ℃.
9. The method according to claim 6, wherein in step S3, the sintering time is 4 to 6 hours; preferably, the sintering temperature is 1400-1500 ℃.
10. The method according to claim 6, wherein in step S3, the press molding is any one of compression molding, extrusion molding, and isostatic pressing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311851808.6A CN117756507A (en) | 2023-12-29 | 2023-12-29 | High-temperature thermal shock resistant high-purity corundum brick and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311851808.6A CN117756507A (en) | 2023-12-29 | 2023-12-29 | High-temperature thermal shock resistant high-purity corundum brick and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117756507A true CN117756507A (en) | 2024-03-26 |
Family
ID=90323780
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311851808.6A Pending CN117756507A (en) | 2023-12-29 | 2023-12-29 | High-temperature thermal shock resistant high-purity corundum brick and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117756507A (en) |
-
2023
- 2023-12-29 CN CN202311851808.6A patent/CN117756507A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10427980B2 (en) | Preparation method of ceramic membrane support | |
| CN108367993A (en) | Fire resisting zircon composite material through sintering, manufacturing method and its purposes | |
| CN103467072B (en) | A kind of preparation method of light microporous corundum ceramic | |
| CN107935608B (en) | Method for preparing zircon brick by using compact zircon aggregate | |
| US20130249136A1 (en) | Cast bodies, castable compositions, and methods for their production | |
| JPH08283073A (en) | Kiln tool | |
| CN110668828B (en) | Magnesium binder for cement-free castable and preparation method thereof | |
| CN106946585B (en) | Method for preparing low-heat-conductivity magnesia-alumina spinel refractory brick by utilizing artificially synthesized microporous spinel | |
| US20240002294A1 (en) | Alkaline porous ceramic matrix and preparation method thereof, electronic-cigarette vaporization core, and electronic cigarette | |
| CN111393156A (en) | Preparation method of cordierite porous ceramic | |
| CN108751998B (en) | Silicon nitride and silicon carbide combined ceramic filter and preparation method thereof | |
| CN109180205B (en) | Chromite refractory material and preparation method thereof | |
| CN117756507A (en) | High-temperature thermal shock resistant high-purity corundum brick and preparation method thereof | |
| RU2756300C1 (en) | Method for manufacturing corundomullite refractory products | |
| CN110452009A (en) | A kind of preparation method of in-situ preparation magnesium aluminate spinel whisker skeletal porous ceramics | |
| CN114394842A (en) | Preparation method of sintered compact high-zirconium brick | |
| CN111302830B (en) | Preparation method of microporous high-temperature-resistant light refractory brick | |
| CN114644525A (en) | Composite sagger added with waste materials and preparation method thereof | |
| CN109053176B (en) | Chromium-containing mullite refractory material and preparation method thereof | |
| CN113149620A (en) | Light mullite-spinel hollow sphere sagger pressurization forming process | |
| CN111592340A (en) | Preparation method of magnesium oxide light heat-insulation brick | |
| CN112573932A (en) | Homogeneous body re-sintered fused zirconia mullite brick and preparation method thereof | |
| EP0704414A1 (en) | Alumina fiber granules, process for producing the granules and a process for producing a porous article using the granules | |
| WO2010023813A1 (en) | Method for manufacturing silicon nitride-bonded sic refractory material | |
| JP2010202472A (en) | Ceramic fired body and method of manufacturing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |