Novel casting powder with rapid melting and efficient inclusion adsorption functions and preparation method of novel casting powder

Abstract

The invention relates to the technical field of fluxing agents, in particular to novel casting powder with rapid melting and efficient inclusion adsorption functions and a preparation method thereof, and the novel casting powder comprises the following components: 30-50 parts by weight of wollastonite, 20-35 parts by weight of silicon dioxide, 5-15 parts by weight of modified boron oxide, 3-8 parts by weight of a regulator, 2-6 parts by weight of boron nitride and 3-8 parts by weight of graphite. Vinyltriethoxysilane is added, and molecules of the vinyltriethoxysilane can be adsorbed on the surface of the casting powder to reduce the surface tension of the casting powder, so that the casting powder is easier to spread and flow at high temperature, the melting speed is increased, a uniform liquid slag layer is formed, and the protection effect is improved; besides, unsaturated chemical bonds exist on silicon atoms in vinyltriethoxysilane, the chemical bonds and inclusions in molten metal can be subjected to chemical reaction or physical adsorption, more active sites are provided for adsorption of the inclusions, and therefore the capacity of capturing and removing the inclusions of the casting powder is improved.

Description

Technical Field

[0001] The invention relates to the technical field of flux, in particular to a novel protective slag with the functions of rapid melting and efficient inclusion absorption and a preparation method thereof. Background Art

[0002] In the iron and steel metallurgical process, protective slag is an indispensable key material in the continuous casting process. Its main functions include preventing oxidation of the molten steel surface, providing lubrication, promoting the adsorption and removal of inclusions, and improving heat transfer performance. Traditional protective slag is usually composed of inorganic compounds such as calcium oxide (CaO) and aluminum oxide (Al2O3). These components cover the surface of the molten steel by forming a slag layer, thereby protecting the molten steel and optimizing its performance.

[0003] However, traditional mold slag has the problem of long melting time, which results in the inability to quickly form an effective liquid slag layer to play a protective role during the continuous casting process. In view of this, we propose a new type of mold slag with rapid melting and efficient inclusion adsorption function and its preparation method. Summary of the invention

[0004] The purpose of the present invention is to provide a new type of protective slag with the functions of rapid melting and efficient inclusion adsorption and a preparation method thereof, so as to solve the problem of long melting time of traditional protective slag mentioned in the above background technology, resulting in the inability to quickly form an effective liquid slag layer to play a protective role during the continuous casting process.

[0005] To achieve the above object, the present invention provides a new type of protective slag with the functions of rapid melting and efficient inclusion absorption, comprising the following components: 30-50 parts by weight of wollastonite, 20-35 parts by weight of silicon dioxide, 5-15 parts by weight of modified boron oxide, 3-8 parts by weight of a regulator, 2-6 parts by weight of boron nitride and 3-8 parts by weight of graphite; The modified boron oxide is prepared by surface-modifying the boron oxide with vinyltriethoxysilane and adding sodium pyrophosphate.

[0006] Preferably, the preparation method of the modified boron oxide is as follows: S1.1. Weigh the following components in parts by weight respectively: 50-80 parts by weight of boron oxide, 5-15 parts by weight of vinyltriethoxysilane, 1-5 parts by weight of dispersant, 3-10 parts by weight of sodium pyrophosphate and 10-30 parts by weight of ethanol; S1.2, heating the boron oxide in a muffle furnace to 150-200° C. and drying for 2-4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to the vinyl triethoxysilane solution, adding a dispersant, stirring and reacting at 40-80°C at a speed of 200-500rpm for 2-6h; after the reaction is completed, the sodium pyrophosphate solution is stirred and reacted at a speed of 200-500rpm for 1-3h; Vinyltriethoxysilane undergoes a hydrolysis reaction in the presence of trace amounts of water to generate silanols (Si-OH). These silanol groups can undergo a condensation reaction with the hydroxyl groups (-OH) on the surface of boric oxide to form stable Si-OB bonds, thereby achieving effective coating of the surface of boric oxide. Through surface modification, the dispersibility of boric oxide particles in the protective slag is significantly improved, agglomeration is avoided, and the consistency of the fluxing effect is ensured. The modified boric oxide surface is more organic-friendly, which helps to improve the interfacial bonding between it and the protective slag system containing organic components or other additives, forming a more uniform and stable structure. This structure can melt and fuse with other components faster, promoting the protective slag to quickly form a continuous and stable slag layer covering the surface of the molten steel, effectively preventing oxidation and inclusion contamination. In addition, by improving the dispersion state and surface properties of boric oxide, the adsorption capacity of the protective slag for non-metallic inclusions can be significantly improved, further purifying the molten steel and reducing internal defects in the ingot.

[0007] Sodium pyrophosphate can form stable complexes with metal ions (such as calcium, magnesium, etc.). This property helps to improve the water resistance and stability of the material and reduce or prevent the negative effects of these ions on the material properties. Sodium pyrophosphate solution is alkaline and has a strong pH buffering capacity. It can be used to adjust the pH value of the reaction system to ensure that the reaction conditions are within the optimal range, which not only affects the reaction rate but also improves the quality of the product.

[0008] S1.4. After the reaction is completed, the solid product is separated by a centrifuge and washed with ethanol 2-3 times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 50-80°C for 6-12h to obtain modified boron oxide.

[0009] Preferably, in S1.3, the concentration of the vinyltriethoxysilane solution is 5%-15%.

[0010] Preferably, in S1.3, the dispersant is sorbitan monostearate or polyoxyethylene sorbitan monooleate.

[0011] Preferably, in S1.3, the sodium pyrophosphate solution is prepared by dissolving sodium pyrophosphate in deionized water to obtain a sodium pyrophosphate solution with a concentration of 3%-5%.

[0012] Preferably, in S1.4, the centrifugal speed is 2000-5000 rpm, and the centrifugal time is 10-30 min.

[0013] On the other hand, the present invention provides a method for preparing a novel mold slag having the functions of rapid melting and efficient inclusion absorption, which is used for any one of the novel mold slags having the functions of rapid melting and efficient inclusion absorption as described above, comprising the following steps: S2.1, weigh the following components in parts by weight respectively: 30-50 parts by weight of wollastonite, 20-35 parts by weight of silicon dioxide, 5-15 parts by weight of modified boron oxide, 3-8 parts by weight of a regulator, 2-6 parts by weight of boron nitride and 3-8 parts by weight of graphite; S2.2, calcining wollastonite at 800-1000°C for 2-4h; at the same time, drying silicon dioxide in an oven at 105-110°C for 6-8h to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, regulator, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 300-500rpm for 15-30min; transfer the mixed raw materials into a high-temperature furnace, stir and melt them at 1300-1500℃ at a speed of 100-200rpm for 1-2h; after the melting is completed, keep warm for 10-30min; S2.4. After the heat preservation is completed, the melt is naturally cooled and formed; the cooled melt is crushed and screened through a sieve to obtain a new type of protective slag with the function of rapid melting and efficient adsorption of inclusions.

[0014] Preferably, in S2.3, the regulator is manganese carbonate or calcium fluoride.

[0015] Preferably, in S2.4, the crushing process is performed using a hammer crusher at a speed of 1000-1500 rpm for 5-10 min.

[0016] Preferably, in S2.4, the mesh size of the sieve is 80-120 meshes.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. In the novel protective slag with the functions of rapid melting and efficient inclusion adsorption and the preparation method thereof, vinyltriethoxysilane is added. Since its molecules can be adsorbed on the surface of the protective slag, the surface tension of the protective slag is reduced, so that it is easier to spread and flow at high temperature, the melting speed is accelerated, a uniform liquid slag layer is formed, and the protective effect is improved; in addition, there are unsaturated chemical bonds on the silicon atoms in vinyltriethoxysilane, and these chemical bonds can chemically react or physically adsorb with inclusions in the molten metal, providing more active sites for the adsorption of inclusions, and firmly adsorbing the inclusions in the protective slag, thereby improving the protective slag's ability to capture and remove inclusions.

[0018] 2. In this new type of protective slag with the functions of rapid melting and efficient adsorption of inclusions and its preparation method, the addition of sodium pyrophosphate can significantly reduce the melting point of the protective slag, causing it to melt rapidly and quickly form a uniform slag layer, thereby improving the use efficiency of the protective slag and the protective effect on the molten metal; sodium pyrophosphate also improves the fluidity of the protective slag, allowing it to spread evenly on the surface of the molten metal, effectively covering the molten metal and isolating it from the air, reducing the occurrence of adverse phenomena such as oxidation; in addition, sodium pyrophosphate enhances the adsorption capacity of the protective slag for inclusions, promotes the combination of inclusions and slag and their effective removal, thereby improving the purity of the molten metal and improving the metal quality. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0020] The present invention provides a novel protective slag with the functions of rapid melting and efficient inclusion absorption, comprising the following components: 30-50 parts by weight of wollastonite, 20-35 parts by weight of silicon dioxide, 5-15 parts by weight of modified boron oxide, 3-8 parts by weight of a regulator, 2-6 parts by weight of boron nitride and 3-8 parts by weight of graphite; The modified boron oxide is prepared by surface-modifying the boron oxide with vinyltriethoxysilane and adding sodium pyrophosphate.

[0021] The dispersant is sorbitan monostearate or polyoxyethylene sorbitan monooleate, preferably sorbitan monostearate.

[0022] The regulator is manganese carbonate or calcium fluoride, preferably manganese carbonate.

[0023] Embodiment 1: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1, respectively weigh the following components in parts by weight: 40 parts by weight of wollastonite, 28 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 5 parts by weight of manganese carbonate, 4 parts by weight of boron nitride and 6 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, manganese carbonate, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0024] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 65 parts by weight of boron oxide, 5 parts by weight of vinyl triethoxysilane, 3 parts by weight of sorbitan monostearate, 6 parts by weight of sodium pyrophosphate and 20 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding sorbitan monostearate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0025] Embodiment 2: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1, respectively weigh the following components in parts by weight: 40 parts by weight of wollastonite, 28 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 5 parts by weight of manganese carbonate, 4 parts by weight of boron nitride and 6 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, manganese carbonate, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0026] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 65 parts by weight of boron oxide, 9 parts by weight of vinyl triethoxysilane, 3 parts by weight of sorbitan monostearate, 6 parts by weight of sodium pyrophosphate and 20 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding sorbitan monostearate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0027] Embodiment 3: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1, respectively weigh the following components in parts by weight: 40 parts by weight of wollastonite, 28 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 5 parts by weight of manganese carbonate, 4 parts by weight of boron nitride and 6 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, manganese carbonate, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0028] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 65 parts by weight of boron oxide, 12 parts by weight of vinyl triethoxysilane, 3 parts by weight of sorbitan monostearate, 6 parts by weight of sodium pyrophosphate and 20 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding sorbitan monostearate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0029] Embodiment 4: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1, respectively weigh the following components in parts by weight: 40 parts by weight of wollastonite, 28 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 5 parts by weight of manganese carbonate, 4 parts by weight of boron nitride and 6 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, manganese carbonate, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0030] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 65 parts by weight of boron oxide, 15 parts by weight of vinyl triethoxysilane, 3 parts by weight of sorbitan monostearate, 6 parts by weight of sodium pyrophosphate and 20 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding sorbitan monostearate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0031] Example 5: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1, respectively weigh the following components in parts by weight: 30 parts by weight of wollastonite, 20 parts by weight of silicon dioxide, 5 parts by weight of modified boron oxide, 3 parts by weight of manganese carbonate, 2 parts by weight of boron nitride and 3 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, manganese carbonate, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0032] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 65 parts by weight of boron oxide, 12 parts by weight of vinyl triethoxysilane, 1 part by weight of sorbitan monostearate, 3 parts by weight of sodium pyrophosphate and 10 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding sorbitan monostearate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0033] Embodiment 6: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1, respectively weigh the following components in parts by weight: 30 parts by weight of wollastonite, 20 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 3 parts by weight of manganese carbonate, 2 parts by weight of boron nitride and 3 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, manganese carbonate, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0034] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 65 parts by weight of boron oxide, 12 parts by weight of vinyl triethoxysilane, 1 part by weight of sorbitan monostearate, 3 parts by weight of sodium pyrophosphate and 10 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding sorbitan monostearate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0035] Example 7: A novel mold slag having the functions of rapid melting and efficient inclusion adsorption and a preparation method thereof, comprising the following steps: S2.1, respectively weigh the following components in parts by weight: 30 parts by weight of wollastonite, 20 parts by weight of silicon dioxide, 15 parts by weight of modified boron oxide, 3 parts by weight of manganese carbonate, 2 parts by weight of boron nitride and 3 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, manganese carbonate, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0036] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 65 parts by weight of boron oxide, 12 parts by weight of vinyl triethoxysilane, 1 part by weight of sorbitan monostearate, 3 parts by weight of sodium pyrophosphate and 10 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding sorbitan monostearate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0037] Embodiment 8: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1. Weigh the following components in parts by weight respectively: 40 parts by weight of wollastonite, 28 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 5 parts by weight of calcium fluoride, 4 parts by weight of boron nitride and 6 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, calcium fluoride, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0038] Wherein, the preparation method of modified boron oxide is as follows: S1.1. Weigh the following components in parts by weight respectively: 50 parts by weight of boron oxide, 9 parts by weight of vinyl triethoxysilane, 3 parts by weight of polyoxyethylene sorbitan monooleate, 6 parts by weight of sodium pyrophosphate and 20 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding polyoxyethylene sorbitan monooleate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0039] Embodiment 9: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1. Weigh the following components in parts by weight respectively: 40 parts by weight of wollastonite, 28 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 5 parts by weight of calcium fluoride, 4 parts by weight of boron nitride and 6 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, calcium fluoride, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0040] Wherein, the preparation method of modified boron oxide is as follows: S1.1, respectively weigh the following components in parts by weight: 80 parts by weight of boron oxide, 15 parts by weight of vinyl triethoxysilane, 3 parts by weight of polyoxyethylene sorbitan monooleate, 6 parts by weight of sodium pyrophosphate and 20 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding polyoxyethylene sorbitan monooleate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0041] Embodiment 10: A novel mold slag having the functions of rapid melting and efficient inclusion absorption and a preparation method thereof, comprising the following steps: S2.1. Weigh the following components in parts by weight respectively: 50 parts by weight of wollastonite, 35 parts by weight of silicon dioxide, 10 parts by weight of modified boron oxide, 8 parts by weight of calcium fluoride, 6 parts by weight of boron nitride and 8 parts by weight of graphite; S2.2, calcining wollastonite at 800°C for 4 hours; at the same time, drying silicon dioxide in an oven at 105°C for 8 hours to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, calcium fluoride, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 500 rpm for 30 minutes; transfer the mixed raw materials to a high-temperature furnace, stir and melt them at 1300°C at a speed of 200 rpm for 2 hours; after the melting is completed, keep the temperature for 30 minutes; S2.4. After the insulation is completed, the melt is naturally cooled and formed; the cooled melt is crushed by a hammer crusher at a speed of 1500 rpm for 10 minutes, and screened through a sieve with a mesh size of 100 to obtain a new type of protective slag with rapid melting and efficient inclusion adsorption function.

[0042] Wherein, the preparation method of modified boron oxide is as follows: S1.1. Weigh the following components in parts by weight respectively: 65 parts by weight of boron oxide, 12 parts by weight of vinyl triethoxysilane, 5 parts by weight of polyoxyethylene sorbitan monooleate, 10 parts by weight of sodium pyrophosphate and 30 parts by weight of ethanol; S1.2, heating the boron oxide to 200° C. in a muffle furnace and drying for 4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to a 10% vinyl triethoxysilane solution, adding polyoxyethylene sorbitan monooleate, stirring at 80°C at a speed of 500 rpm for 6 hours; after the reaction is completed, adding a 5% sodium pyrophosphate solution, and continuing to stir at a speed of 400 rpm for 3 hours; S1.4. After the reaction is completed, the solid product is separated by a centrifuge at a speed of 2000 rpm for 30 min, and washed with ethanol three times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 60 ° C for 12 h to obtain modified boron oxide.

[0043] Comparative Example 1: The method of Example 3 was adopted without using modified boron oxide, and boron oxide was directly used to prepare a new type of protective slag with the functions of rapid melting and efficient inclusion adsorption.

[0044] Comparative Example 2: The method of Example 3 was adopted, and the sodium pyrophosphate was removed in the preparation method of modified boron oxide.

[0045] The present invention discloses a novel mold slag having the functions of rapid melting and efficient inclusion absorption, prepared by modified boron oxide. The performance index inspection items and inspection standards of the novel mold slag having the functions of rapid melting and efficient inclusion absorption are as follows: Preheat the high-temperature furnace to 1500℃, weigh 50 grams of new protective slag and put it into a marked crucible; quickly put the crucible with the protective slag into the high-temperature furnace that has been preheated to 1500℃, check the status of the protective slag regularly, and record the time from being placed in the high-temperature furnace to being completely melted and forming a uniform slag layer; the shorter melting time means that the protective slag can melt quickly and spread evenly on the surface of the molten steel at the beginning of the continuous casting process, forming a continuous and stable slag layer.

[0046] Prepare 1 kg of simulated molten steel in a high-temperature furnace and control the temperature at 1500-1600°C, add a predetermined amount of Al2O3 particles to the simulated molten steel (1 gram of Al2O3 particles per liter of molten steel), and stir evenly to simulate the actual molten steel containing inclusions; add new protective slag to the simulated molten steel (50 grams of protective slag per liter of molten steel), and stir thoroughly; after stirring, immediately take a 10 ml sample from the molten steel, quickly cool and preserve it, and calculate the adsorption efficiency of the protective slag on Al2O3 particles according to the formula; high adsorption efficiency indicates that the protective slag has a strong capture ability for non-metallic inclusions, thereby significantly reducing the inclusion content in the molten steel and improving the purity of the steel.

[0047] According to the above standards, the new mold slags with rapid melting and efficient inclusion adsorption functions prepared in the above Examples 1-10 and Comparative Examples 1-2 were tested, and the obtained data are shown in Table 1: Table 1 Performance data of the new mold slag of Examples 1-10 and Comparative Examples 1-2

[0048] It can be seen from Examples 1-4 that: when the mass ratio of vinyltriethoxysilane to boron oxide in the modified boron oxide gradually increases, the melting time of the new protective slag gradually shortens and the adsorption efficiency gradually increases, but when the mass ratio of vinyltriethoxysilane to boron oxide reaches a certain value, the melting time of the new protective slag gradually prolongs and the adsorption efficiency gradually decreases. It can be seen that with the increase of the mass ratio of vinyltriethoxysilane, the melting time and adsorption efficiency of the new protective slag are improved, but excessive increase may prolong the melting time of the new protective slag and reduce the adsorption efficiency; As the proportion of vinyltriethoxysilane increases, more surfaces of boron oxide particles are coated with vinyltriethoxysilane. This coating layer can effectively reduce the agglomeration of boron oxide particles, making the boron oxide more evenly dispersed in the protective slag system; evenly distributed boron oxide can more effectively play its role as a flux, thereby accelerating the melting process of the overall protective slag; boron oxide is easy to volatilize at high temperatures, and after being modified with vinyltriethoxysilane, the formed organic coating layer can prevent the volatilization of boron oxide to a certain extent and maintain its concentration in the protective slag stable, which not only helps to quickly form a uniform slag layer, but also ensures that boron oxide continues to play a role in the entire continuous casting process.

[0049] The ethoxy group in vinyltriethoxysilane can be hydrolyzed under certain conditions to generate silanol (Si-OH). These silanol groups can undergo condensation reaction with the hydroxyl group (-OH) on the surface of boric oxide to form Si-OB bonds, thereby achieving effective coating of the surface of boric oxide. This chemical bonding enhances the interaction between boric oxide and other components, and improves the stability of the entire protective slag system. The surface of the modified boric oxide particles has better hydrophilicity and higher active sites, which is conducive to capturing inclusions in the molten steel. In addition, it is easier to form some special microstructures or active sites, which can better adsorb and fix inclusions in the molten steel, further purify the molten steel, and reduce internal defects of the ingot.

[0050] Further, by comparing Examples 5-7, it can be seen that when other components remain unchanged, only when the proportion of modified boron oxide gradually increases, the melting time of the new protective slag gradually shortens and the adsorption efficiency gradually increases. It can be seen that boron oxide, as a flux in the protective slag, has a significant effect of reducing the melting point and improving the melting performance. When the proportion of modified boron oxide increases, it is equivalent to introducing more low-melting point substances into the protective slag system, thereby reducing the melting point of the entire protective slag system, making it easier to reach a melting state during the heating process, and shortening the melting time; In addition, modified boron oxide may synergize with other fluxes in the protective slag to enhance the fluxing effect. As its proportion increases, this synergistic effect is more significant, which promotes the melting of refractory components in the protective slag; modified boron oxide has a large specific surface area and rich surface active groups. As its proportion increases, the active surface available for adsorption of inclusions in the protective slag increases. These active surfaces can interact with inclusions through physical adsorption (such as van der Waals force, electrostatic attraction) and chemical adsorption (such as chemical bonding), thereby improving the adsorption capacity of inclusions.

[0051] It can be seen from Example 3 in combination with Examples 8-9 that when the mass ratio of vinyltriethoxysilane to boron oxide remains unchanged, increasing the weight of boron oxide gradually shortens the melting time of the new protective slag and has a significant effect on the adsorption efficiency.

[0052] It can be seen from Example 3 and Comparative Example 1 that when the modified boron oxide is not used and the new protective slag with the function of rapid melting and efficient inclusion adsorption is prepared directly using boron oxide, the melting time of the new protective slag is significantly prolonged and the adsorption efficiency is significantly reduced; Boric oxide itself will form a relatively stable boron-oxygen tetrahedron or boron-oxygen triangle network structure. In the absence of modification, this network structure is relatively dense and the bond energy between molecules is high. During the heating process, more energy is needed to break these chemical bonds and change the substance from solid to liquid, so the melting time will be significantly prolonged. When using boric oxide directly, due to its relatively few surface active sites, it mainly relies on its own oxygen atoms and boron atoms to interact with inclusions, the adsorption capacity is limited, and the adsorption efficiency is significantly reduced. In contrast, modified boric oxide can increase a large number of active sites by introducing other elements or groups. These active sites can more effectively react chemically or physically adsorb with inclusions. Therefore, modified boric oxide exhibits a lower melting point and faster melting speed during the melting process, and is also more efficient in adsorbing inclusions.

[0053] Taking Example 3 as the best example and combining it with Comparative Example 2, it can be seen that in the preparation method of modified boron oxide, when sodium pyrophosphate is removed, the melting time of the new protective slag is significantly prolonged and the adsorption efficiency is significantly reduced; Sodium pyrophosphate changes the chemical bonding state and intermolecular forces inside the melt, promoting the formation of a structure that is more conducive to rapid melting, thereby reducing the melting point of the protective slag; after removing sodium pyrophosphate, the melt structure becomes unfavorable for rapid melting, the intermolecular bonding force is enhanced, and a higher temperature or longer heating time is required to achieve melting, resulting in a significant extension of the melting time; sodium pyrophosphate can also reduce the interfacial tension between the slag and the inclusions, making it easier for the slag to contact and adsorb the inclusions; after removing sodium pyrophosphate, the interfacial tension increases, the contact between the slag and the inclusions becomes difficult, and the adsorption efficiency decreases; in addition, sodium pyrophosphate provides a specific ionic environment in the slag, which helps to change the surface charge properties of the inclusions, making them easier to be adsorbed by the slag. After removing sodium pyrophosphate, the ionic environment changes, which is not conducive to the adjustment of the surface properties of the inclusions, thereby reducing the adsorption efficiency.

[0054] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A new type of mold slag with rapid melting and efficient inclusion absorption function, characterized in that: The invention comprises the following components: 30-50 parts by weight of wollastonite, 20-35 parts by weight of silicon dioxide, 5-15 parts by weight of modified boron oxide, 3-8 parts by weight of a regulator, 2-6 parts by weight of boron nitride and 3-8 parts by weight of graphite; The modified boron oxide is prepared by surface-modifying the boron oxide with vinyltriethoxysilane and adding sodium pyrophosphate.

2. The novel mold slag with rapid melting and efficient inclusion adsorption function according to claim 1 is characterized in that: The preparation method of the modified boron oxide is as follows: S1.

1. Weigh the following components in parts by weight respectively: 50-80 parts by weight of boron oxide, 5-15 parts by weight of vinyltriethoxysilane, 1-5 parts by weight of dispersant, 3-10 parts by weight of sodium pyrophosphate and 10-30 parts by weight of ethanol; S1.2, heating the boron oxide in a muffle furnace to 150-200° C. and drying for 2-4 hours to remove moisture and other impurities adsorbed on the surface to obtain pretreated boron oxide; S1.3, adding the pretreated boron oxide to the vinyl triethoxysilane solution, adding a dispersant, stirring and reacting at 40-80°C at a speed of 200-500 rpm for 2-6 hours; after the reaction is completed, adding the sodium pyrophosphate solution, and continuing to stir and react at a speed of 200-500 rpm for 1-3 hours; S1.

4. After the reaction is completed, the solid product is separated by a centrifuge and washed with ethanol 2-3 times to remove unreacted vinyltriethoxysilane, sodium pyrophosphate and other impurities; the washed product is dried in a vacuum drying oven at 50-80°C for 6-12h to obtain modified boron oxide.

3. The novel mold slag with rapid melting and efficient inclusion adsorption function according to claim 2 is characterized in that: In the S1.3, the concentration of the vinyltriethoxysilane solution is 5%-15%.

4. The novel mold slag with rapid melting and efficient inclusion adsorption function according to claim 2 is characterized in that: In the above S1.3, the dispersant is sorbitan monostearate or polyoxyethylene sorbitan monooleate.

5. The novel mold slag with rapid melting and efficient inclusion adsorption function according to claim 2 is characterized in that: In S1.3, the sodium pyrophosphate solution is prepared by dissolving sodium pyrophosphate in deionized water to obtain a sodium pyrophosphate solution with a concentration of 3% to 5%.

6. The novel mold slag with rapid melting and efficient inclusion adsorption function according to claim 2 is characterized in that: In S1.4, the centrifugal speed is 2000-5000 rpm, and the centrifugal time is 10-30 min.

7. A method for preparing a new type of mold slag with the function of rapid melting and efficient inclusion absorption, which is used to prepare the new type of mold slag with the function of rapid melting and efficient inclusion absorption as claimed in any one of claims 1 to 6, characterized in that: The preparation method of the novel mold slag with the functions of rapid melting and efficient inclusion adsorption is as follows: S2.1, weigh the following components in parts by weight respectively: 30-50 parts by weight of wollastonite, 20-35 parts by weight of silicon dioxide, 5-15 parts by weight of modified boron oxide, 3-8 parts by weight of a regulator, 2-6 parts by weight of boron nitride and 3-8 parts by weight of graphite; S2.2, calcining wollastonite at 800-1000°C for 2-4h; at the same time, drying silicon dioxide in an oven at 105-110°C for 6-8h to obtain pretreated wollastonite and silicon dioxide; S2.3, put the pretreated wollastonite and silicon dioxide, modified boron oxide, regulator, boron nitride and graphite into a high-speed mixer, and mix them thoroughly at a speed of 300-500rpm for 15-30min; transfer the mixed raw materials into a high-temperature furnace, stir and melt them at 1300-1500℃ at a speed of 100-200rpm for 1-2h; after the melting is completed, keep warm for 10-30min; S2.4, after the heat preservation is completed, the melt is naturally cooled and formed; The cooled melt is crushed and screened through a sieve to obtain a new type of protective slag with the functions of rapid melting and efficient inclusion absorption.

8. The method for preparing a novel mold slag having the functions of rapid melting and efficient inclusion adsorption according to claim 7, characterized in that: In the above S2.3, the regulator is manganese carbonate or calcium fluoride.

9. The method for preparing a novel mold slag having the functions of rapid melting and efficient inclusion adsorption according to claim 7, characterized in that: In S2.4, the crushing process is performed using a hammer crusher at a speed of 1000-1500 rpm for 5-10 minutes.

10. The method for preparing a novel mold slag having the functions of rapid melting and efficient inclusion adsorption according to claim 7, characterized in that: In the S2.4, the mesh size of the sieve is 80-120 meshes.

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