Calcium-silicon-aluminum submersed nozzle lining material and application

Abstract

The invention discloses a calcium-silicon-aluminum submersed nozzle lining material which comprises the following components in percentage by mass: 80-93% of a base material; 5-15% of an additive; 1.5%-5% of a composite binding agent; the base material comprises CaO-SiO2-Al2O3 ternary components, and the CaO-SiO2-Al2O3 ternary components are distributed in a range limited by a connecting line of four specific points A, B, C and D of a CaO-SiO2-Al2O3 ternary phase diagram and two liquidus lines at 1600 DEG C and 1700 DEG C; the method can be applied to the submersed nozzle of the continuous casting crystallizer, can also be applied to the high-temperature-resistant industry fields such as blockage prevention of a long nozzle of a steel ladle adopting aluminum deoxidized steel and anti-nodulation of a stopper rod of a tundish, and solves the problem that the submersed nozzle is easy to nodulate and block in the pouring process of aluminum deoxidized steel such as an automobile sheet at present; the volume density of the calcium-silicon-aluminum submersed nozzle lining material is 2.65-3.20 g / cm < 3 >, the apparent porosity is 10-15%, and the thermal shock resistance is gt; and 10 times (1100 DEG C-water cooling) are carried out, and the number of continuous casting furnaces in the actual use process is 8-15 times.

Description

Technical Field

[0001] This invention belongs to the field of steelmaking continuous casting technology, specifically relating to an immersion nozzle lining material and its application. Background Technology

[0002] Submerged entry nozzles (Submerged entry nozzles) are one of the "three major components" in continuous casting and are crucial functional materials. They are positioned between the tundish and the crystallizer during use. Currently, the mainstream submerged entry nozzles fall into three main categories: fused silica nozzles, alumina-carbon nozzles, and alumina-carbon-zirconium-carbon composite nozzles. Each has its advantages and disadvantages. For example, fused silica nozzles have poor corrosion resistance when casting special steels such as manganese steel. Alumina-carbon nozzles have poor resistance to protective slag erosion and thermal shock, and due to their poor thermal conductivity, they can cause slag buildup and alumina inclusions, leading to nozzle blockage and severely affecting continuous casting. In alumina-carbon-zirconium-carbon composite nozzles, CaO-stabilized zirconium dioxide undergoes calcium oxide desolvation, causing instability and fragmentation of the stabilized zirconium oxide, thus exacerbating erosion at the slag line. Meanwhile, during the production of ultra-low carbon automotive steel, aluminum-carbon and aluminum-carbon-zirconium-carbon sprues commonly develop nozzle nodules. To improve this phenomenon, the material must be modified.

[0003] In the published literature, Japanese Patent (Japanese Patent Application Publication No. 4-224061) and Chinese Patent (CN1062248C) proposed a CaO-ZrO2-C lining material and a material to prevent alumina blockage. Both patents utilize the fact that alumina can easily react with CaO or calcium fluoride in the lining material to form a low-melting-point phase, thereby reducing alumina deposition. However, in actual use, the anti-blocking effect is not good as the casting time increases. Subsequently, Chinese patent (CN100352579C) proposed an anti-clogging submersible nozzle body material. This improved aluminum-zirconium-carbon nozzle material is formed by directly adding silane and silicon nitride to the body to replace a portion of the alumina and ZrO2. However, in practical use, the oxidation of silicon nitride to form SiO2 has an adverse effect on the actual casting process. While this material shows some effectiveness in the initial stages of casting, as casting progresses, the inner wall of the nozzle still suffers from the long-standing problems of Al-C nozzles, such as poor resistance to protective slag erosion and the adhesion of slag and alumina inclusions, leading to nozzle blockage. Therefore, researching and developing novel anti-clogging materials for submersible nozzles to reduce blockage in continuous casting is of great significance for improving continuous casting production efficiency. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a calcium-silicon-aluminum submersible nozzle lining material, which features excellent anti-clogging performance and long service life. It can be applied not only to submersible nozzles in continuous casting molds but also to high-temperature industries such as anti-clogging of long nozzles in ladles using aluminum deoxidized steel and anti-nodulation of tundish stopper rods. This overcomes the current problem of nodulation and clogging of submersible nozzles made of aluminum deoxidized steel, such as those used in automotive steel casting, and is expected to be widely adopted for large-scale production applications.

[0005] To achieve the above objectives, the following technical solution is adopted: A calcium-silicon-aluminum immersion nozzle liner material, the composition of which is as follows by mass percentage: Matrix material: 80%-93%; Additives: 5-15%; Composite binder: 1.5%-5%; The matrix material comprises a ternary composition of CaO-SiO2-Al2O3; wherein the proportions of CaO, SiO2, and Al2O3 are within the range defined by the lines connecting points A, B, C, and D in the CaO-SiO2-Al2O3 ternary phase diagram; wherein point A has a composition of 3 wt% Al2O3, 82 wt% SiO2, and 15 wt% CaO; point B has a composition of 6 wt% Al2O3, 80 wt% SiO2, and 14 wt% CaO; point C has a composition of 3 wt% Al2O3, 72 wt% SiO2, and 25 wt% CaO; and point D has a composition of 2 wt% Al2O3, 72 wt% SiO2, and 26 wt% CaO.

[0006] In the optimized scheme, the ratio of CaO, SiO2, and Al2O3 is between the two liquidus lines of 1600℃ and 1700℃ in the CaO-SiO2-Al2O3 ternary phase diagram.

[0007] According to the above scheme, the proportion of each raw material in the matrix material is calculated based on the composition of the ternary phase diagram. The raw materials of the matrix material are selected from corundum, calcium sand, sintered dolomite sand, silica, and quartz. The particle size composition of the matrix material is as follows: 3-1mm 20-30%, 1-0.5mm 30-40%, 0.5-0.088mm 20-35%, and less than 0.088mm 10-15%.

[0008] According to the above scheme, the additive is one or a combination of several of MgAlON, AlON, SiAlON and MgAl2O4; the particle size range is 1-0.5mm 35-65%, 0.5-0.088mm 35-65%.

[0009] According to the above scheme, the composite binder is composed of metal oxides, rare earth elements, and boron / carbon / nitrides mixed in a mass ratio of (2-5):1:(1-3); the particle size of the composite binder is less than 500μm.

[0010] According to the above scheme, the metal oxide is one or more of Fe2O3, TiO2 and ZrO2 combined in any proportion.

[0011] According to the above scheme, the rare earth elements are La2O3 (lanthanum oxide), CeO2 (cerium oxide), and Pr6O. 11 It is composed of one or more of praseodymium oxide and Nd2O3 (neodymium oxide) in any proportion.

[0012] According to the above scheme, the boron / carbon / nitride is one or more of B4C, BN, CaB6, MgB2, ZrB2, Si3N4 and SiC combined in any proportion.

[0013] The present invention also provides an anti-clogging submersible nozzle, comprising an outer layer, a body and an inner liner, wherein the inner liner is sintered from the above-mentioned calcium-silicon-aluminum submersible nozzle liner material, and the thickness of the inner liner after sintering is 10-15mm; the outer layer material is refractory fiber, and the body material is aluminum-carbon, zirconium-carbon or aluminum-zirconium-carbon.

[0014] The present invention also provides a method for preparing the above-mentioned anti-clogging submersible inlet, comprising the following steps: (1) Select the matrix material, additives and composite binder according to the design ratio of the calcium-silicon-aluminum immersion nozzle liner material mentioned above, and mix them to obtain the liner material; (2) The inner lining material and the sprue body material are laid out in the manner of first arranging the body and then arranging the inner lining material, and then formed by isostatic pressing. (3) Sintering treatment is carried out by nitrogen protection, argon protection, or carbon embedding sintering; (4) After sintering, the pre-made refractory fiber is bound to the outside of the nozzle body with a high-temperature adhesive to form an outer heat insulation structure, and finally an anti-clogging immersion nozzle is obtained.

[0015] According to the above scheme, in step (1), a planetary ball mill is used for mixing. The mixing is carried out by alternating forward and reverse rotation, with a rotation speed of 200-350 r / min. The direction is changed every 5 minutes, and the mixing time is 30-60 minutes.

[0016] According to the above scheme, the pressure of isostatic pressing in step (2) is between 200-350MPa, and the holding time is 15-35min.

[0017] According to the above scheme, the sintering temperature in step (3) is 1550~1650℃ and the holding time is 3.5-6h.

[0018] According to the above scheme, the refractory fiber in step (4) is aluminum silicate fiber or alumina fiber.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: The anti-clogging principle of the anti-clogging lining material of this invention is to design the components in the phase diagram region. In actual production, due to the increased enrichment of alumina, it reacts with the anti-clogging material. According to the phase diagram principle, the reaction products will move along the line connecting the composition design point and Al2O3 to the low melting point region. Driven by the steel flow, they will melt and enter the crystallizer, so that alumina does not accumulate on the inner wall of the nozzle, thereby eliminating nozzle blockage.

[0020] The additives are one or a combination of several of MgAlON, AlON, SiAlON, and MgAl2O4. Since AlON has low wettability with molten steel, using MgAlON, AlON, SiAlON, and MgAl2O4 as second-phase additives can improve the slag erosion resistance of the lining material. Meanwhile, Al2O3 is trigonal, while AlON is primarily spinel cubic, resulting in a high interfacial energy between them. This prevents Al2O3 inclusions in the molten steel from accumulating on the surface of the lining material during high-temperature operation, thereby reducing nozzle clogging.

[0021] The composite binder is composed of metal oxides, rare earth elements, and boron / carbon / nitrides mixed in a mass ratio of (2-5):1:(1-3). The addition of the composite binder helps improve the thermal shock resistance and corrosion resistance of the lining material. The combination of metal oxides and rare earth elements "purifies" the grain boundaries by forming rare earth aluminosilicate phases, thereby improving the high-temperature strength and creep resistance of the grain boundaries and also regulating the melting point of the grain boundaries. The addition of boron / carbon / nitrides improves the oxidation resistance and thermal shock resistance of the lining material by forming a protective film on its surface. Simultaneously, the oxides in the composite binder enhance the tightness of the nozzle through high-temperature fluxing, reducing porosity and indirectly improving the hydration resistance of the lining material.

[0022] This invention relates to a calcium-silicon-aluminum submersible nozzle lining material, which features excellent anti-clogging performance and long service life. It can be applied not only to submersible nozzles in continuous casting molds but also to high-temperature industries such as anti-clogging of long nozzles in ladles using aluminum deoxidized steel and anti-nodulation of tundish stopper rods. This overcomes the current problem of nodulation and clogging in submersible nozzles made of aluminum deoxidized steel, such as those used in automotive steel casting, and holds promise for large-scale production application.

[0023] The bulk density of the calcium-silicon-aluminum submersible nozzle liner material of this invention is 2.65-3.20 g / cm³.3 Apparent porosity 10-15%, thermal shock stability >10 cycles (1100℃-water cooling), and 8-15 consecutive casting cycles in actual use. Attached Figure Description

[0024] Figure 1 The ternary phase ratio used in this invention falls within the range of the CaO-SiO2-Al2O3 ternary phase diagram.

[0025] Figure 2 : Schematic diagram of the anti-clogging immersion nozzle structure for the crystallizer of this invention.

[0026] Figure 3 The position of the ternary phase ratios used in Examples 1-4 in the CaO-SiO2-Al2O3 ternary phase diagram.

[0027] Figure 4 Example 3: SEM micrograph of the cross-section of the calcium-silicon-aluminum immersion nozzle liner. Detailed Implementation

[0028] The following embodiments further illustrate the technical solution of the present invention, but are not intended to limit the scope of protection of the present invention.

[0029] A specific embodiment provides a calcium-silicon-aluminum immersion nozzle liner material, the matrix material of which uses a ternary phase ratio within the range of the CaO-SiO2-Al2O3 ternary phase diagram (see attached figure). Figure 1 As shown. The matrix material composition of the calcium-silicon-aluminum lining material is located in... Figure 1 The yellow area in the phase diagram is the composition-controlled region consisting of two liquidus lines at 1600℃ and 1700℃, and points A, B, C, and D. Point A has the following composition: Al₂O₃ 3wt%, SiO₂ 82wt%, and CaO 15wt%; point B has: Al₂O₃ 6wt%, SiO₂ 80wt%, and CaO 14wt%; point C has: Al₂O₃ 3wt%, SiO₂ 72wt%, and CaO 25wt%; and point D has: Al₂O₃ 2wt%, SiO₂ 72wt%, and CaO 26wt%.

[0030] The matrix material accounts for 80%-93% of the total matrix material, and the proportion of each raw material in the matrix material is calculated based on the composition points of the phase diagram. In specific embodiments, the available matrix materials are: corundum (Al2O3% content greater than 95%), calcium sand (CaO content greater than 94%), or a mixture of calcium sand and sintered dolomite sand (CaO>55%, CaO+MgO content greater than 92%), and silica or quartz (SiO2 content greater than 95%). The particle size distribution of the matrix material is as follows: 3-1mm 20-30%, 1-0.5mm 30-40%, 0.5-0.088mm 20-35%, and less than 0.088mm 10-15%.

[0031] The additives comprise 5-15% of the total composition, consisting of one or more of MgAlON, AlON, SiAlON, and MgAl2O4. The particle sizes of the additives are as follows: 1-0.5 mm (35-65%), 0.5-0.088 mm (35-65%).

[0032] The composite binder accounts for 1.5%-5% of the total composition. The composite binder is composed of oxides, rare earth elements, and boron / carbon / nitrides added in a ratio of (2-5):1:(1-3). The oxides are one or more of Fe2O3, TiO2, and ZrO2 combined in any proportion. The rare earth elements are La2O3 (lanthanum oxide), CeO2 (cerium oxide), and Pr6O2. 11 The composite binder is composed of one or more of praseodymium oxide and Nd2O3 (neodymium oxide) in any proportion, and the boron / carbon / nitride is composed of one or more of B4C, BN, CaB6, MgB2, ZrB2, Si3N4, and SiC in any proportion. The particle size of the composite binder is less than 500 μm.

[0033] A specific embodiment provides an anti-clogging immersion water inlet for a crystallizer, the structural schematic diagram of which is attached. Figure 2 As shown, it includes an outer layer, a body, and an inner lining. The inner lining is made of the aforementioned calcium-silicon-aluminum lining material and is sintered. After sintering, the inner lining thickness is 10-15 mm. The outer layer is a certain thickness of refractory fiber (aluminosilicate fiber or alumina fiber). The body is usually aluminum-carbon, zirconium-carbon, or aluminum-zirconium-carbon.

[0034] The specific implementation also provides a method for preparing the above-mentioned submersible nozzle: The matrix material, additives, and composite binder are selected and directly mixed according to the designed composition and particle size distribution. In the optimized scheme, a planetary ball mill is used for mixing, with alternating forward and reverse rotation at a speed of 200-350 r / min, changing direction every 5 minutes, for a mixing time of 30-60 minutes. The mixed lining material and the nozzle body material are then laid out in a manner that prioritizes the body material followed by the lining mixture. Isostatic pressing is then used for molding, with a molding pressure between 200-350 MPa and a holding time of 15-35 minutes. Subsequently, the submerged nozzle is prepared using nitrogen protection, argon protection, or carbon sintering. The final sintering temperature is 1550-1650℃, with a holding time of 3.5-6 hours. After sintering, the lining material thickness must be 10-15 mm. After the main body and inner lining composite materials are sintered, the pre-made refractory fibers are then bound to the outside of the nozzle body with a high-temperature adhesive to form an outer insulation structure, ultimately resulting in a clog-resistant immersion nozzle that can be used in actual production.

[0035] Example 1 (1) By designing the CaO-SiO2-Al2O3 ternary phase diagram, the components of the anti-clogging lining material are located in the CaO-SiO2-Al2O3 ternary phase diagram. Figure 3 The yellow area at point E in the phase diagram has the following composition: Al2O3 content 4wt%, SiO2 content 84wt%, and CaO content 12wt%.

[0036] (2) Selection of matrix material: The matrix material accounts for 90% of the composition. The corresponding raw materials are selected according to the composition at point E. Corundum 4wt% (Al2O3% content 96%), calcium sand and sintered dolomite sand are prepared in a 1:1 ratio, totaling 12wt%, of which calcium sand (CaO content 95%), sintered dolomite (CaO>58%, CaO+MgO content 94%) and quartz 84wt% (SiO2 content 96%) are used. The particle size distribution of the matrix material is as follows: 3-1mm 24%, 1-0.5mm 36%, 0.5-0.088mm 30%, and less than 0.088mm 10%.

[0037] (3) Additives: 7%, MgAlON and AlON are added in a 1:1 ratio. The particle size of the additives is as follows: 1-0.5mm 60%, 0.5-0.088mm 40%.

[0038] (4) Composite binder: 3%, the composite binder is composed of oxides:rare earths:boron / carbon / nitrides in a ratio of 4:1:2, wherein the oxides are prepared by Fe2O3 and TiO2 in a 1:1 ratio, the rare earths are prepared by La2O3, CeO2 and Nd2O3 in a 1:1:1 ratio, and the boron / carbon / nitrides are prepared by B4C, ZrB2 and Si3N4 in a 1:2:1 ratio. The particle size of the composite binder is 350μm.

[0039] (5) In this embodiment, the inner lining is the above-mentioned material, the outer layer is alumina ceramic fiber, and the body is aluminum carbon.

[0040] (6) Preparation of lining mixture: Select matrix materials, additives and composite binders according to the designed composition points and particle size distribution, and mix them using a planetary ball mill. The mixing is carried out by alternating forward and reverse rotation at a speed of 230 r / min, changing the direction every 5 min, and the mixing time is 45 min.

[0041] (7) The mixed lining material and the body material are laid out in the manner of first laying the body and then laying the lining mixture. Then, the mixture is formed by isostatic pressing with a molding pressure of 250 MPa and a holding time of 20 min.

[0042] (8) Subsequently, the immersion nozzle was prepared by sintering under nitrogen protection. The final sintering temperature was 1560℃ and the holding time was 4h. After sintering, the thickness of the inner lining material must be 12mm.

[0043] (9) After the main body and the inner lining combined material are sintered, the pre-made alumina ceramic fiber is then bound to the outside of the water nozzle body with a high-temperature adhesive to form an outer heat insulation structure, and finally an anti-clogging immersion water nozzle that can be used in actual production is obtained.

[0044] (10) Performance testing of anti-clogging lining material: The bulk density of this type of anti-clogging material was tested to be 2.7 g / cm³. 3 It has an apparent porosity of 11%, thermal shock resistance of 12 cycles (1100℃-water cooling), and 9 consecutive casting cycles during actual use.

[0045] Example 2 (1) By designing the CaO-SiO2-Al2O3 ternary phase diagram, the components of the anti-clogging lining material are located in the CaO-SiO2-Al2O3 ternary phase diagram. Figure 3 The yellow area F in the phase diagram has the following composition: Al2O3 content 3.5wt%, SiO2 content 81.5wt%, and CaO content 15wt%.

[0046] (2) Selection of matrix material: The matrix material accounts for 88% of the composition. The corresponding raw materials are selected according to the composition at point F. Corundum 3.5wt% (Al2O3% content 96%), calcium sand and sintered dolomite sand are configured in a 2:1 ratio, totaling 15wt%, of which calcium sand (CaO content 95.5%), sintered dolomite (CaO>58%, CaO+MgO content 95%) and quartz 81.5wt% (SiO2 content 96%). The particle size distribution of the matrix material is as follows: 3-1mm 28%, 1-0.5mm 35%, 0.5-0.088mm 27%, and less than 0.088mm 10%.

[0047] (3) Additives: 10%, MgAlON and AlON are added in a 1:1 ratio. The particle size of the additives is as follows: 1-0.5mm 60%, 0.5-0.088mm 40%.

[0048] (4) Composite binder: 2%, the composite binder is composed of oxides: rare earths: boron / carbon / nitrides in a ratio of 2:1:3, wherein the oxides are prepared by TiO2 and ZrO2 in a ratio of 2:1, the rare earths are prepared by La2O3 and CeO2 in a ratio of 1:1, and the boron / carbon / nitrides are prepared by MgB2, ZrB2 and Si3N4 in a ratio of 2:2:1. The particle size of the composite binder is 300μm.

[0049] (5) In this embodiment, the inner lining is the above-mentioned material, the outer layer is alumina ceramic fiber, and the body is aluminum zirconium carbon.

[0050] (6) Preparation of lining mixture: Select matrix materials, additives and composite binders according to the designed composition points and particle size distribution, and mix them using a planetary ball mill. The mixing is carried out by alternating forward and reverse rotation at a speed of 300 r / min, changing the direction every 5 min, and the mixing time is 35 min.

[0051] (7) The mixed lining material and the body material are laid out in the manner of first arranging the body and then arranging the lining mixture. Then, the mixture is formed by isostatic pressing with a molding pressure of 270 MPa and a holding time of 18 min.

[0052] (8) Subsequently, the immersion nozzle was prepared by sintering under nitrogen protection. The final sintering temperature was 1580℃ and the holding time was 4h. After sintering, the thickness of the inner lining material must be 13mm.

[0053] (9) After the main body and the inner lining combined material are sintered, the pre-made alumina ceramic fiber is then bound to the outside of the water nozzle body with a high-temperature adhesive to form an outer heat insulation structure, and finally an anti-clogging immersion water nozzle that can be used in actual production is obtained.

[0054] (10) Performance testing of anti-clogging lining material: The bulk density of this type of anti-clogging material was tested to be 2.8 g / cm³. 3 It has an apparent porosity of 12%, thermal shock resistance of 14 cycles (1100℃-water cooling), and 11 consecutive casting cycles during actual use.

[0055] Example 3 (1) By designing the CaO-SiO2-Al2O3 ternary phase diagram, the components of the anti-clogging lining material are located in the CaO-SiO2-Al2O3 ternary phase diagram. Figure 3 The yellow area G in the phase diagram has the following composition: Al2O3 content 3wt%, SiO2 content 78.5wt%, and CaO content 18.5wt%.

[0056] (2) Selection of matrix material: The matrix material accounts for 85% of the composition, and the corresponding raw materials are selected according to the composition of point G. Corundum 3wt% (Al2O3% content 97%), calcium sand 18.5wt% (CaO content 96%), and silica 78.5wt% (SiO2 content 96%). Among them, the particle size distribution of the matrix material is as follows: 3-1mm 26%, 1-0.5mm 37%, 0.5-0.088mm 25%, and less than 0.088mm 12%.

[0057] (3) Additives: 12%, MgAlON, SiAlON and AlON were added in a combination of 1:1:1. The particle sizes of the additives are as follows: 1-0.5mm 63%, 0.5-0.088mm 37%.

[0058] (4) Composite binder: 3%, the composite binder is composed of oxides: rare earths: boron / carbon / nitrides in a ratio of 2:1:2, wherein the oxides are prepared by Fe2O3 and TiO2 in a 1:1 ratio, and the rare earths are prepared by Pr6O 11 CeO2 and Nd2O3 were prepared in a 1:1:1 ratio, and boron / carbon / nitride was prepared from B4C, BN, and ZrB2 in a 1:1:2 ratio. The composite binder had a particle size of 250 μm.

[0059] (5) In this embodiment, the inner lining is the above-mentioned material, the outer layer is aluminum silicate ceramic fiber, and the body is aluminum zirconium carbon.

[0060] (6) Preparation of lining mixture: Select matrix materials, additives and composite binders according to the designed composition points and particle size distribution, and mix them using a planetary ball mill. The mixing is carried out by alternating forward and reverse rotation at a speed of 300 r / min, changing the direction every 5 min, and the mixing time is 35 min.

[0061] (7) The mixed lining material and the body material are laid out in the manner of first arranging the body and then arranging the lining mixture. Then, the mixture is formed by isostatic pressing with a molding pressure of 310 MPa and a holding time of 17 min.

[0062] (8) Subsequently, the immersion nozzle was prepared by sintering under argon protection. The final sintering temperature was 1600℃ and the holding time was 5h. After sintering, the thickness of the inner lining material should be 13mm.

[0063] (9) After the main body and the inner lining combined material are sintered, the pre-made aluminum silicate ceramic fiber is then bound to the outside of the water nozzle body with a high-temperature adhesive to form an outer heat insulation structure, and finally an anti-clogging immersion water nozzle that can be used in actual production is obtained.

[0064] (10) Performance testing of anti-clogging lining material: The bulk density of this type of anti-clogging material was tested to be 2.95 g / cm³. 3 It has an apparent porosity of 13%, thermal shock resistance of 13 cycles (1100℃-water cooling), and 13 consecutive casting cycles in actual use.

[0065] The SEM micrograph of the cross-section of the anti-clogging submersible nozzle liner obtained in this embodiment is attached. Figure 4 As shown in the figure, there are few pores between the phases, and they are tightly bound together through interfacial bonding.

[0066] Example 4 (1) By designing the CaO-SiO2-Al2O3 ternary phase diagram, the components of the anti-clogging lining material are located in the CaO-SiO2-Al2O3 ternary phase diagram. Figure 3 The yellow area H in the phase diagram has the following composition: Al2O3 content 2.5wt%, SiO2 content 74.5wt%, and CaO content 23wt%.

[0067] (2) Selection of matrix material: The matrix material accounts for 83% of the composition, and the corresponding raw materials are selected according to the composition at point H. Corundum 2.5wt% (Al2O3% content 97%), calcium sand 23wt% (CaO content 96%), and quartz 74.5wt% (SiO2 content 96.5%). Among them, the particle size distribution of the matrix material is as follows: 3-1mm 24%, 1-0.5mm 36%, 0.5-0.088mm 27%, and less than 0.088mm 13%.

[0068] (3) Additives: 13%, SiAlON, AlON and MgAl2O4 were added in a combination of 2:2:1. The particle sizes of the additives are as follows: 1-0.5mm 50%, 0.5-0.088mm 50%.

[0069] (4) Composite binder: 4%, the composite binder is composed of oxides: rare earths: boron / carbon / nitrides in a ratio of 2:1:3, wherein the oxides are prepared by Fe2O3 and ZrO2 in a 1:1 ratio, the rare earths are prepared by La2O3, CeO2 and Nd2O3 in a 1:1:1 ratio, and the boron / carbon / nitrides are prepared by B4C, CaB2, ZrB2 and Si3N4 in a 1:1:2:1 ratio. The composite binder has a particle size of 350μm.

[0070] (5) In this embodiment, the inner lining is the above-mentioned material, the outer layer is alumina ceramic fiber, and the body is aluminum carbon.

[0071] (6) Preparation of lining mixture: Select matrix materials, additives and composite binders according to the designed composition points and particle size distribution, and mix them using a planetary ball mill. The mixing is carried out by alternating forward and reverse rotation at a speed of 320 r / min, changing the direction every 5 min, and the mixing time is 45 min.

[0072] (7) The mixed lining material and the body material are laid out in the manner of first laying the body and then laying the lining mixture. Then, the mixture is formed by isostatic pressing with a molding pressure of 310 MPa and a holding time of 25 min.

[0073] (8) Subsequently, the submerged nozzle was prepared by sintering with carbon. The final sintering temperature was 1620℃ and the holding time was 5h. After sintering, the thickness of the inner lining material must be 13mm.

[0074] (9) After the main body and the inner lining combined material are sintered, the pre-made alumina ceramic fiber is then bound to the outside of the water nozzle body with a high-temperature adhesive to form an outer heat insulation structure, and finally an anti-clogging immersion water nozzle that can be used in actual production is obtained.

[0075] (10) Performance testing of anti-clogging lining material: The bulk density of this type of anti-clogging material was tested to be 3.1 g / cm³. 3 It has an apparent porosity of 13%, thermal shock resistance of 12 cycles (1100℃-water cooling), and 12 consecutive casting cycles in actual use.

[0076] Comparative Example 1 Repeat Example 1, with the CaO-SiO2-Al2O3 ternary phase designed with Al2O3 content of 3.45wt%, SiO2 content of 88.96wt%, and CaO content of 7.59wt%, and the rest of the process remains unchanged.

[0077] The lining material was tested and found to have a bulk density of 2.6 g / cm³. 3 It has an apparent porosity of 13%, thermal shock resistance of 8 cycles (1100℃-water cooling), and 5 consecutive casting cycles during actual use.

[0078] Comparative Example 2 Repeat Example 1, except that the composite binder is replaced with a silica sol binder, and the rest of the process remains the same.

[0079] The lining material was tested and found to have a bulk density of 2.45 g / cm³. 3 It has an apparent porosity of 23%, thermal shock resistance of 4 cycles (1100℃-water cooling), and two consecutive casting cycles during actual use.

[0080] Comparative Example 3 Repeat Example 1, but omit the addition of the additives, while keeping the rest of the process unchanged.

[0081] The lining material was tested and found to have a bulk density of 2.53 g / cm³. 3 It has an apparent porosity of 15%, thermal shock resistance of 3 cycles (1100℃-water cooling), and has been continuously cast in 3 furnaces during actual use.

Claims

1. A calcium-silicon-aluminum immersion nozzle liner material, characterized in that... The composition, expressed as a percentage by mass, is as follows: Matrix material: 80%-93%; Additives: 5-15%; Composite binder: 1.5%-5%; The matrix material comprises a ternary composition of CaO-SiO2-Al2O3; wherein the proportions of CaO, SiO2, and Al2O3 are within the range defined by the lines connecting points A, B, C, and D in the CaO-SiO2-Al2O3 ternary phase diagram; wherein point A has a composition of 3 wt% Al2O3, 82 wt% SiO2, and 15 wt% CaO; point B has a composition of 6 wt% Al2O3, 80 wt% SiO2, and 14 wt% CaO; point C has a composition of 3 wt% Al2O3, 72 wt% SiO2, and 25 wt% CaO; and point D has a composition of 2 wt% Al2O3, 72 wt% SiO2, and 26 wt% CaO.

2. The calcium-silicon-aluminum immersion nozzle liner material as described in claim 1, characterized in that... The ratio of CaO, SiO2, and Al2O3 lies between the two liquidus lines at 1600℃ and 1700℃ in the CaO-SiO2-Al2O3 ternary phase diagram.

3. The calcium-silicon-aluminum immersion nozzle liner material as described in claim 1, characterized in that... The proportions of each raw material in the matrix material are calculated based on the composition of the ternary phase diagram. The raw materials of the matrix material are selected from corundum, calcium sand, sintered dolomite sand, silica, and quartz. The particle size distribution of the matrix material is as follows: 3-1mm 20-30%, 1-0.5mm 30-40%, 0.5-0.088mm 20-35%, and less than 0.088mm 10-15%.

4. The calcium-silicon-aluminum immersion nozzle liner material as described in claim 1, characterized in that... The additive is one or a combination of several of MgAlON, AlON, SiAlON and MgAl2O4; the particle size range of the additive is 1-0.5mm 35-65%, 0.5-0.088mm 35-65%.

5. The calcium-silicon-aluminum immersion nozzle liner material as described in claim 1, characterized in that... The composite binder is composed of metal oxides, rare earth elements, and boron, carbon, and nitrides mixed in a mass ratio of (2-5):1:(1-3); the particle size of the composite binder is less than 500 μm.

6. The calcium-silicon-aluminum immersion nozzle liner material as described in claim 5, characterized in that... The metal oxide is one or more of Fe2O3, TiO2 and ZrO2 combined in any proportion.

7. The calcium-silicon-aluminum immersion nozzle liner material as described in claim 5, characterized in that... The rare earth elements are La2O3, CeO2, and Pr6O. 11 It is composed of one or more of Nd2O3 in any proportion.

8. The calcium-silicon-aluminum immersion nozzle liner material as described in claim 5, characterized in that... The boron / carbon / nitride is one or more of B4C, BN, CaB6, MgB2, ZrB2, Si3N4 and SiC in any proportion.

9. A clog-resistant immersion water inlet, characterized in that... It includes an outer layer, a body, and an inner lining, wherein the inner lining is sintered from the calcium-silicon-aluminum immersion nozzle lining material described in claim 1, and the thickness of the inner lining after sintering is 10-15mm; the outer layer material is refractory fiber, and the body material is aluminum-carbon, zirconium-carbon, or aluminum-zirconium-carbon.

10. The method for preparing the anti-clogging submersible water inlet according to claim 9, characterized in that... Includes the following steps: (1) Select the matrix material, additives and composite binder according to the design ratio of the calcium-silicon-aluminum immersion nozzle liner material above, and mix them to obtain the liner material; (2) The inner lining material and the sprue body material are laid out in the manner of first arranging the body and then arranging the inner lining material, and then formed by isostatic pressing. (3) Sintering treatment is carried out by nitrogen protection, argon protection, or carbon embedding sintering; (4) After sintering, the pre-made refractory fiber is bound to the outside of the nozzle body with a high-temperature adhesive to form an outer heat insulation structure, and finally an anti-clogging immersion nozzle is obtained.

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