Integrated forming preparation method of Sialon combined silicon carbide blast furnace taphole mud sleeve

Abstract

The invention belongs to the technical field of refractory materials, and particularly relates to an integral forming preparation method of a Sialon combined silicon carbide blast furnace taphole mud sleeve. Silicon carbide coarse, medium and fine particles, silicon carbide micro powder, aluminum oxide micro powder, metal silicon powder and metal aluminum powder are used as main raw materials, uniformly dispersed slurry is obtained through ball milling, the slurry is poured into a pre-assembled mold with an inner cavity integrally communicated, an integrated mud sleeve blank is obtained through a gel injection molding method, and the integrated mud sleeve is manufactured. A sialon binding phase is formed through an in-situ reaction in a nitrogen atmosphere, and then the sintering temperature is further increased, so that the sialon-bound silicon carbide blast furnace taphole mud sleeve is obtained. The prepared iron notch mud sleeve can replace existing mud sleeves of castable, prefabricated parts and the like, is used for a blast furnace iron notch, and effectively solves the problems that the existing mud sleeve is short in service life, frequent in maintenance, high in labor intensity, prominent in potential safety hazards and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of refractory materials, and particularly relates to a method for integrally forming a Sialon-bonded silicon carbide blast furnace iron mouth mud sleeve. Background Art

[0002] The blast furnace is currently the mainstream iron-making equipment and process. Its lifespan is an important factor determining the smelting cost, and the key to the longevity of the blast furnace is the hearth. The blast furnace iron mouth is an important part of the blast furnace iron-making process where molten iron is discharged from the blast furnace hearth, and it is a weak link that restricts the lifespan of the hearth. Due to the intermittent nature of iron tapping, an opening machine is required to break the tapping mud to open the iron mouth before tapping, and after tapping is completed, a mud tapping machine and tapping mud are required to block the iron mouth, and this cycle is repeated frequently. The iron mouth mud sleeve is an important component set on the blast furnace iron mouth to cooperate with opening and blocking.

[0003] Existing blast furnace iron mouth mud sleeves are mostly made of castables or prefabricated parts, primarily made of corundum, mullite, and silicon carbide. For example, patent CN 104291844 B discloses a method for preparing an iron mouth mud sleeve castable, then pouring it into an iron mouth mud sleeve mold and baking it to obtain an iron mouth mud sleeve prefabricated part made of corundum, mullite, laterite nickel ore, and silicon carbide. Patent CN 110615688 B discloses a method for preparing low-cost blast furnace iron mouth mud sleeve prefabricated parts using various recycled materials through vibration casting and low-temperature baking. Because both the castable and the prefabricated part are refractory materials that are dried and baked only at low temperatures, regardless of the material used, they generally suffer from low density, high porosity, low strength, and poor resistance to slag and iron corrosion. During service, the mud sleeve is prone to slag adhesion and breakage, and furnace gas leakage, resulting in a short iron mouth mud sleeve lifespan, frequent maintenance, high labor intensity, and significant safety hazards.

[0004] Sialon combined with silicon carbide refractory materials has the characteristics of high strength, oxidation resistance, thermal shock resistance, and excellent erosion resistance. It is mainly used in the blast furnace waist, bosh and other parts. From the perspective of material alone, it is also expected to be used in the blast furnace iron mouth mud sleeve. Since the shapes of the furnace waist and bosh refractory materials are relatively simple, they are mostly prepared using relatively mature vibration pressurization and high-temperature firing processes. The blast furnace iron mouth mud sleeve is not only complex in shape, but also has extremely high requirements for sealing during service. Therefore, splicing and assembly must be avoided as much as possible to avoid gaps. However, it is very challenging to achieve integrated molding and preparation of complex-shaped mud sleeves: vibration pressurization is prone to insufficient pressure transmission and poor uniformity in various parts. The outer surface of the isostatically pressed sample requires secondary processing, which is inefficient and costly, and is not conducive to its application and promotion in the steel industry. Summary of the Invention

[0005] The purpose of the present invention is to propose an integrated molding preparation method of a Sialon-combined silicon carbide blast furnace iron mouth mud sleeve, so that the mud sleeve prepared by the present invention can be used for the blast furnace iron mouth, replacing the current non-high-temperature fired refractory mud sleeves such as castables and prefabricated parts.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions: A method for integrally forming a Sialon-silicon carbide iron mouth mud sleeve for a blast furnace is disclosed. First, a gel injection molding method is used to achieve the integrated molding of the iron mouth mud sleeve with a complex shape. Second, metallic silicon powder and metallic aluminum powder begin to partially oxidize during the medium-temperature debinding stage to form highly active silicon oxide and aluminum oxide. Third, during the subsequent in-situ reaction process, the emergence of the highly active phase will enhance the reaction with nitrogen and the intermediate product silicon nitride, forming more Sialon phases, improving the bonding with silicon carbide, and achieving high density and high strength. The specific process steps of the preparation method are as follows: (1) Preparation of slurry: Use silicon carbide coarse, medium and fine particles, silicon carbide powder, alumina powder, metallic silicon powder and metallic aluminum powder as main raw materials, add water, dispersant, organic monomer and cross-linking agent, and perform ball milling to obtain a uniformly dispersed slurry, which is then transferred to a material barrel; (2) Forming of the blank: Taking advantage of the rapid solidification and molding characteristics of gel casting, an initiator and a catalyst are sequentially added to the slurry prepared in step (1), and after continued stirring, the slurry is poured into a pre-assembled mold with an integrally connected inner cavity, so that the monomer and the cross-linking agent undergo a polymerization reaction, thereby achieving rapid solidification and molding of the slurry. After disassembling the mold and demoulding, an integrated molded body is obtained; (3) Sintering of mud sleeve: The green body is first placed in an oven for drying; then transferred to an atmosphere sintering electric furnace, and the ceramic mud sleeve is sintered according to a certain sintering system; under the protection of a nitrogen atmosphere, it is naturally cooled with the furnace to complete the sintering process, and a Sialon-bonded silicon carbide blast furnace iron mouth mud sleeve is obtained.

[0007] The main raw materials are coarse, medium and fine silicon carbide particles, silicon carbide micropowder, alumina micropowder, metallic silicon powder and metallic aluminum powder, and their respective mass proportions are: medium silicon carbide particles account for 6-8 parts, fine silicon carbide particles account for 10-16 parts, silicon carbide micropowder accounts for 3-4 parts, alumina micropowder accounts for 6-7 parts, metallic silicon powder accounts for 12-18 parts, metallic aluminum powder accounts for 2-3 parts, and the balance of coarse silicon carbide particles accounts for 44-61 parts.

[0008] The added amounts of water, dispersant, organic monomer and cross-linking agent respectively account for 40-48%, 0.6-1.0%, 2-5% and 0.2-0.5% of the total mass of the main raw materials.

[0009] The initiator and catalyst are sequentially added to the slurry prepared in step (1), with the added amounts accounting for 4-6% and 0.8-1.2% of the mass of the organic monomer, respectively.

[0010] The particle sizes of the coarse, medium and fine silicon carbide particles are 1-0.5 mm, 0.5-0.3 mm and 0.3-0.1 mm respectively; the particle size of the silicon carbide micropowder is 800-2000 mesh; the particle size of the alumina micropowder is 800-2000 mesh; the particle size of the metallic silicon powder is 200-325 mesh; and the particle size of the metallic aluminum powder is 200-400 mesh.

[0011] The dispersant is ammonium polyacrylate or tetramethylammonium hydroxide, the organic monomer is acrylamide or methacrylamide, and the cross-linking agent is N,N'-methylenebisacrylamide or methyl acrylate.

[0012] The initiator is ammonium persulfate, and the catalyst is N,N,N',N'-tetramethylethylenediamine.

[0013] The ball milling parameters for preparing the slurry are: using alumina balls as the ball milling medium, the ball mill speed is 200-300 rpm, and the ball milling time is 40-80 minutes.

[0014] The process parameters for drying in the oven are: oven temperature of 110-130° C., and heat preservation for 12-18 hours.

[0015] The sintering system in the atmosphere sintering electric furnace is as follows: first, heating to 600-800°C at a heating rate of 1-3°C / min in an air atmosphere, and keeping warm for 2-4 hours; after evacuating, introducing a nitrogen atmosphere and maintaining a slightly positive pressure, heating to 1300-1350°C at a heating rate of 0.5-1°C / min, and keeping warm for 8-10 hours; then continuing to heat to 1400-1550°C at a heating rate of 1-2°C / min, and keeping warm for 3-5 hours.

[0016] The present invention proposes an integrated molding preparation method for a Sialon-combined silicon carbide blast furnace iron mouth mud sleeve, which uses coarse, medium and fine silicon carbide particles, silicon carbide micropowder, alumina micropowder, metallic silicon powder and metallic aluminum powder as main raw materials, pours the evenly dispersed slurry obtained by ball milling and mixing into a pre-assembled mold with an integrally connected inner cavity, obtains an integrated mud sleeve blank by a gel injection molding method, and generates a Sialon phase in situ by a high-temperature sintering process in a nitrogen atmosphere to achieve the combination of silicon carbide and other components, and synergistically improve the density, mechanical properties and corrosion resistance of the material; the iron mouth mud sleeve proposed by the present invention can replace the existing blast furnace iron mouth castables and prefabricated mud sleeves, and effectively make up for their shortcomings such as low density, high porosity, low strength and poor resistance to slag iron corrosion, thereby solving the problems of short iron mouth mud sleeve life, frequent maintenance, high labor intensity and prominent safety hazards. DETAILED DESCRIPTION

[0017] The present invention will be described with reference to the following embodiments: Example 1:

[0018] A ball mill was added to a jar containing 480g of water, 6g of ammonium polyacrylate (dispersant), 50g of methacrylamide (organic monomer), 5g of methyl acrylate (crosslinker), 440g of coarse silicon carbide particles, 80g of medium particles, 160g of fine particles, 40g of 1100-mesh silicon carbide micropowder, 70g of 800-mesh alumina micropowder, 180g of 200-mesh metallic silicon powder, and 30g of 325-mesh metallic aluminum powder. The mixture was ball-milled at 300 rpm for 40 minutes using alumina balls as the milling medium. The mixed slurry was then transferred to a material bucket. During the stirring process, 2.0g of ammonium persulfate and 0.4g of N,N,N′,N′-tetramethylethylenediamine were added. The mixture was then quickly poured into a pre-assembled mold with a connected inner cavity. After the slurry solidified and formed, the mold was disassembled and demolded to obtain an integrated green body.

[0019] Place the green body in an oven and dry it at 110°C for 18 hours to remove moisture. Then transfer it to an atmosphere sintering electric furnace, first heat it to 600°C at a heating rate of 2°C / min in an air atmosphere, keep it warm for 4 hours, remove organic matter while oxidizing silicon powder and aluminum powder; after vacuuming, introduce nitrogen atmosphere and maintain a slightly positive pressure, heat it to 1350°C at a heating rate of 1°C / min, keep it warm for 9 hours; then heat it to 1450°C at a heating rate of 2°C / min, keep it warm for 3 hours. Cool it naturally with the furnace to obtain a one-piece iron mouth mud sleeve of Sialon combined with silicon carbide. After testing, the volume density is 2.78g / cm 3 , the flexural strength is 33.9MPa. Example 2:

[0020] A ball mill was added to a jar containing 460g of water, 7g of tetramethylammonium hydroxide (TMAH), 40g of acrylamide (organic monomer), 4g of N,N′-methylenebisacrylamide (crosslinker), 487g of coarse silicon carbide particles, 75g of medium particles, 145g of fine particles, 37g of 800-mesh silicon carbide micropowder, 68g of 1100-mesh alumina micropowder, 165g of 270-mesh metallic silicon powder, and 23g of 400-mesh metallic aluminum powder. The mixture was milled at 200 rpm for 80 minutes using alumina balls as the milling medium. The resulting slurry was then transferred to a material bucket. During the stirring process, 2.0g of ammonium persulfate and 0.4g of N,N,N′,N′-tetramethylethylenediamine were added. The mixture was then quickly poured into a pre-assembled mold with a fully connected inner cavity. After the slurry solidified and formed, the mold was disassembled and demolded to obtain a fully integrated green body.

[0021] Place the green body in an oven and dry it at 130°C for 12 hours to remove moisture. Then transfer it to an atmosphere sintering electric furnace, first heat it to 700°C at a heating rate of 1°C / min in an air atmosphere, keep it warm for 3 hours, remove organic matter while oxidizing silicon powder and aluminum powder; after vacuuming, introduce nitrogen atmosphere and maintain a slightly positive pressure, heat it to 1300°C at a heating rate of 0.5°C / min, keep it warm for 10 hours; then heat it to 1550°C at a heating rate of 1.5°C / min, keep it warm for 4 hours. Cool it naturally in the furnace to obtain a one-piece iron mouth mud sleeve of Sialon combined with silicon carbide. After testing, the volume density is 2.85g / cm 3 , the flexural strength is 40.5MPa. Example 3:

[0022] A ball mill was added to a jar containing 440g of water, 8g of ammonium polyacrylate (dispersant), 30g of acrylamide (organic monomer), 3g of methyl acrylate (crosslinker), 525g of coarse silicon carbide particles, 70g of medium particles, 130g of fine particles, 35g of 2000-mesh silicon carbide micropowder, 65g of 1600-mesh alumina micropowder, 150g of 325-mesh metallic silicon powder, and 25g of 270-mesh metallic aluminum powder. The mixture was ball-milled at 250 rpm for 60 minutes using alumina balls as the milling medium. The resulting slurry was then transferred to a material bucket. During the stirring process, 1.8g of ammonium persulfate and 0.36g of N,N,N′,N′-tetramethylethylenediamine were added. The mixture was then quickly poured into a pre-assembled mold with a fully connected inner cavity. After the slurry solidified and formed, the mold was disassembled and demolded to obtain an integrated green body.

[0023] Place the green body in an oven and dry it at 110°C for 18 hours to remove moisture. Then transfer it to an atmosphere sintering electric furnace, first heat it to 800°C at a heating rate of 3°C / min in an air atmosphere, keep it warm for 2 hours, remove organic matter while oxidizing silicon powder and aluminum powder; after vacuuming, introduce nitrogen atmosphere and maintain a slightly positive pressure, heat it to 1350°C at a heating rate of 1°C / min, keep it warm for 8 hours; then heat it to 1450°C at a heating rate of 2°C / min, keep it warm for 3 hours. Cool it naturally with the furnace to obtain a one-piece iron mouth mud sleeve of Sialon combined with silicon carbide. After testing, the volume density is 2.82g / cm 3 , the flexural strength is 34.5MPa. Example 4:

[0024] A ball mill was added to a jar containing 420g of water, 9g of tetramethylammonium hydroxide (TMAH), 20g of methacrylamide (OM), 2g of N,N′-methylenebisacrylamide (MBA), 562g of coarse silicon carbide particles, 65g of medium silicon carbide particles, 115g of fine silicon carbide particles, 32g of 1600-mesh silicon carbide micropowder, 63g of 2000-mesh alumina micropowder, 135g of 200-mesh metallic silicon powder, and 28g of 200-mesh metallic aluminum powder. The mixture was milled at 300 rpm for 40 minutes using alumina balls. The resulting slurry was then transferred to a material bucket. During the stirring process, 1.2g of ammonium persulfate and 0.24g of N,N,N′,N′-tetramethylethylenediamine were added. The mixture was then quickly poured into a pre-assembled mold with a fully connected inner cavity. After the slurry solidified and formed, the mold was disassembled and demolded to obtain a fully integrated green body.

[0025] Place the green body in an oven and dry it at 130°C for 12 hours to remove moisture. Then transfer it to an atmosphere sintering electric furnace, first heat it to 700°C at a heating rate of 2°C / min in an air atmosphere, keep it warm for 3 hours, remove organic matter while oxidizing silicon powder and aluminum powder; after vacuuming, introduce nitrogen atmosphere and maintain a slightly positive pressure, heat it to 1300°C at a heating rate of 0.5°C / min, keep it warm for 10 hours; then heat it to 1550°C at a heating rate of 1°C / min, keep it warm for 5 hours. Cool it naturally with the furnace to obtain a one-piece iron mouth mud sleeve of Sialon combined with silicon carbide. After testing, the volume density is 2.88g / cm 3 , the flexural strength is 43.3MPa. Example 5:

[0026] Add 400 g of water, 10 g of dispersant ammonium polyacrylate, 50 g of organic monomer acrylamide, 5 g of cross-linking agent N,N′-methylenebisacrylamide, 610 g of coarse silicon carbide particles, 60 g of medium particles, 100 g of fine particles, 30 g of 1600 mesh silicon carbide micropowder, 60 g of 800 mesh alumina micropowder, 120 g of 270 mesh metallic silicon powder, and 20 g of 400 mesh metallic aluminum powder into a ball mill jar. Use alumina balls as ball milling media and ball mill at a speed of 200 rpm for 80 minutes. Transfer the mixed slurry to a material bucket; add 2.5 g of ammonium persulfate and 0.5 g of N,N,N′,N′-tetramethylethylenediamine during stirring; then quickly pour it into a pre-assembled mold with an integrally connected inner cavity. After the slurry is solidified and formed, disassemble the mold and demold it to obtain an integrated molded body.

[0027] Place the green body in an oven and dry it at 120°C for 15 hours to remove moisture. Then transfer it to an atmosphere sintering electric furnace, first heat it to 600°C at a heating rate of 1°C / min in an air atmosphere, keep it warm for 4 hours, remove organic matter and oxidize silicon powder and aluminum powder; after vacuuming, introduce nitrogen atmosphere and maintain a slightly positive pressure, heat it to 1300°C at a heating rate of 1°C / min, keep it warm for 8 hours; then heat it to 1500°C at a heating rate of 1.5°C / min, keep it warm for 4 hours. Cool it naturally with the furnace to obtain a one-piece iron mouth mud sleeve of Sialon combined with silicon carbide. After testing, the volume density is 2.85g / cm 3 , the flexural strength is 38.8MPa. Example 6:

[0028] Add 440g of water, 8g of dispersant tetramethylammonium hydroxide, 40g of organic monomer methacrylamide, 4g of crosslinking agent propylene methyl acrylate, 517g of coarse silicon carbide particles, 65g of medium particles, 160g of fine particles, 35g of 2000-mesh silicon carbide micropowder, 63g of 1100-mesh alumina micropowder, 135g of 325-mesh metallic silicon powder, and 25g of 270-mesh metallic aluminum powder into a ball mill jar. Use alumina balls as ball milling media and ball mill at a speed of 300 rpm for 40 minutes. Transfer the mixed slurry to a material bucket; add 1.6g of ammonium persulfate and 0.32g of N,N,N′,N′-tetramethylethylenediamine during stirring; then quickly pour it into a pre-assembled mold with an integrally connected inner cavity. After the slurry is cured and formed, disassemble the mold and demold it to obtain an integrated molded body.

[0029] Place the green body in an oven and dry it at 110°C for 18 hours to remove moisture. Then transfer it to an atmosphere sintering electric furnace, first heat it to 800°C at a heating rate of 2°C / min in an air atmosphere, keep it warm for 2 hours, remove organic matter while oxidizing silicon powder and aluminum powder; after vacuuming, introduce nitrogen atmosphere and maintain a slightly positive pressure, heat it to 1350°C at a heating rate of 0.5°C / min, keep it warm for 9 hours; then heat it to 1450°C at a heating rate of 2°C / min, keep it warm for 3 hours. Cool it naturally with the furnace to obtain a one-piece iron mouth mud sleeve of Sialon combined with silicon carbide. After testing, the volume density is 2.83g / cm 3 , the flexural strength is 37.6MPa. Example 7:

[0030] A ball mill was added to a jar containing 480g of water, 6g of ammonium polyacrylate (dispersant), 30g of acrylamide (organic monomer), 3g of N,N′-methylenebisacrylamide (crosslinker), 498g of coarse silicon carbide particles, 75g of medium particles, 130g of fine particles, 37g of 800-mesh silicon carbide micropowder, 65g of 1600-mesh alumina micropowder, 165g of 270-mesh metallic silicon powder, and 30g of 325-mesh metallic aluminum powder. The mixture was milled at 250 rpm for 60 minutes using alumina balls as the milling medium. The resulting slurry was then transferred to a material bucket. During the stirring process, 1.5g of ammonium persulfate and 0.3g of N,N,N′,N′-tetramethylethylenediamine were added. The mixture was then quickly poured into a pre-assembled mold with a fully connected inner cavity. After the slurry solidified and formed, the mold was disassembled and demolded to obtain a fully integrated green body.

[0031] Place the green body in an oven and dry it at 120°C for 15 hours to remove moisture. Then transfer it to an atmosphere sintering electric furnace, first heat it to 600°C at a heating rate of 3°C / min in an air atmosphere, keep it warm for 4 hours, remove organic matter while oxidizing silicon powder and aluminum powder; after vacuuming, introduce nitrogen atmosphere and maintain a slightly positive pressure, heat it to 1300°C at a heating rate of 1°C / min, keep it warm for 10 hours; then heat it to 1550°C at a heating rate of 1°C / min, keep it warm for 5 hours. Cool it naturally with the furnace to obtain a one-piece iron mouth mud sleeve of Sialon combined with silicon carbide. After testing, the volume density is 2.79g / cm 3 , the flexural strength is 32.3MPa.

Claims

1. A method for integrally forming a blast furnace iron mouth sleeve made of Sialon and silicon carbide. First, a gel casting method is used to achieve integral molding of the iron mouth sleeve with a complex shape. Secondly, metallic silicon powder and metallic aluminum powder begin to partially oxidize during the medium-temperature debinding stage to form highly active silicon oxide and aluminum oxide; Thirdly, during the later in-situ reaction process, the emergence of the highly active phase will intensify the reaction with nitrogen and the intermediate product silicon nitride, forming more Sialon phases and improving the bonding with silicon carbide, thus achieving high density and high strength. The specific process steps of the preparation method are as follows: (1) Preparation of slurry: Use silicon carbide coarse, medium and fine particles, silicon carbide powder, alumina powder, metallic silicon powder and metallic aluminum powder as main raw materials, add water, dispersant, organic monomer and cross-linking agent, and perform ball milling to obtain a uniformly dispersed slurry, which is then transferred to a material barrel; (2) Forming of the blank: Taking advantage of the rapid solidification and molding characteristics of gel casting, an initiator and a catalyst are sequentially added to the slurry prepared in step (1), and after continued stirring, the slurry is poured into a pre-assembled mold with an integrally connected inner cavity, so that the monomer and the cross-linking agent undergo a polymerization reaction, thereby achieving rapid solidification and molding of the slurry. After disassembling the mold and demoulding, an integrated molded body is obtained; (3) Sintering of mud sleeve: The green body is first placed in an oven for drying; then transferred to an atmosphere sintering electric furnace, and the ceramic mud sleeve is sintered according to a certain sintering system; under the protection of a nitrogen atmosphere, it is naturally cooled with the furnace to complete the sintering process, and a Sialon-bonded silicon carbide blast furnace iron mouth mud sleeve is obtained.

2. The method for integrally forming a Sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The main raw materials are coarse, medium and fine silicon carbide particles, silicon carbide micropowder, alumina micropowder, metallic silicon powder and metallic aluminum powder, and their respective mass proportions are: medium silicon carbide particles account for 6-8 parts, fine silicon carbide particles account for 10-16 parts, silicon carbide micropowder accounts for 3-4 parts, alumina micropowder accounts for 6-7 parts, metallic silicon powder accounts for 12-18 parts, metallic aluminum powder accounts for 2-3 parts, and the balance of coarse silicon carbide particles accounts for 44-61 parts.

3. The method for integrally forming a sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The added amounts of water, dispersant, organic monomer and cross-linking agent respectively account for 40-48%, 0.6-1.0%, 2-5% and 0.2-0.5% of the total mass of the main raw materials.

4. The method for integrally forming a Sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The initiator and catalyst are sequentially added to the slurry prepared in step (1), with the added amounts accounting for 4-6% and 0.8-1.2% of the mass of the organic monomer, respectively.

5. The method for integrally forming a sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The particle sizes of the coarse, medium and fine silicon carbide particles are 1-0.5 mm, 0.5-0.3 mm and 0.3-0.1 mm respectively; the particle size of the silicon carbide micropowder is 800-2000 mesh; the particle size of the alumina micropowder is 800-2000 mesh; the particle size of the metallic silicon powder is 200-325 mesh; and the particle size of the metallic aluminum powder is 200-400 mesh.

6. The method for integrally forming a sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The dispersant is ammonium polyacrylate or tetramethylammonium hydroxide, the organic monomer is acrylamide or methacrylamide, and the cross-linking agent is N,N'-methylenebisacrylamide or methyl acrylate.

7. The method for integrally forming a sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The initiator is ammonium persulfate, and the catalyst is N,N,N',N'-tetramethylethylenediamine.

8. The method for integrally forming a sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The ball milling parameters for preparing the slurry are: using alumina balls as the ball milling medium, the ball mill speed is 200-300 rpm, and the ball milling time is 40-80 minutes.

9. The method for integrally forming a sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The process parameters for drying in the oven are: oven temperature of 110-130° C., and heat preservation for 12-18 hours.

10. The method for integrally forming a sialon-silicon carbide-bonded blast furnace iron mouth mud sleeve according to claim 1, characterized in that: The sintering system in the atmosphere sintering electric furnace is as follows: first, heating to 600-800°C at a heating rate of 1-3°C / min in an air atmosphere, and keeping warm for 2-4 hours; after evacuating, introducing a nitrogen atmosphere and maintaining a slightly positive pressure, heating to 1300-1350°C at a heating rate of 0.5-1°C / min, and keeping warm for 8-10 hours; then continuing to heat to 1400-1550°C at a heating rate of 1-2°C / min, and keeping warm for 3-5 hours.