A process for smelting ferrotitanium by aluminothermic method based on composite aluminium charge
By using a composite aluminum material process with modified Li2B4O7 and fluoride-MgO composite additives, the problem of reduced titanium recovery rate caused by easy oxidation of aluminum scrap was solved, and efficient smelting and purity improvement of titanium-iron alloys were achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JINZHOU GUOTAI IND CO LTD
- Filing Date
- 2026-03-10
- Publication Date
- 2026-06-16
Smart Images
Figure CN121802190B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of titanium-iron alloy smelting technology, specifically a process for smelting titanium-iron alloys using the aluminothermic method based on composite aluminum materials. Background Technology
[0002] Ferrotitanium alloys have a wide range of applications in steel production, serving as deoxidizers, denitrifiers, and alloying additives. The ladle process for producing ferrotitanium alloys requires the use of highly reactive aluminum particles to reduce less reactive titanium metal from its oxides (titanium concentrate) and then fuse it with metals such as iron, aluminum, and silicon to obtain the ferrotitanium alloy.
[0003] While some aluminum granules can be replaced by industrial waste such as cold-worked aluminum shavings, these shavings are thin and elongated. On one hand, these small shavings are easily blown away by hot air currents or prematurely oxidized and burned when added to high-temperature furnace charge or in the early stages of the reaction, resulting in unnecessary aluminum loss and environmental pollution. On the other hand, their large surface area makes them highly susceptible to oxidation during processing and storage, forming a dense Al2O3 film on their surface. This film hinders the reaction, resulting in an actual effective aluminum content participating in reduction that is far lower than the theoretical value. This leads to insufficient reducing agent and problems such as difficulty in initiating the reaction, uneven heat release, and incomplete reduction, ultimately causing a sharp drop in titanium recovery rate. Summary of the Invention
[0004] (1) Technical problems to be solved
[0005] The purpose of this invention is to provide a process for smelting titanium-iron alloys using the aluminothermic method based on composite aluminum materials, in order to solve the problem of reduced titanium recovery rate caused by replacing some aluminum particles with aluminum shavings.
[0006] (2) Technical solution
[0007] To achieve the above objectives, on the one hand, the present invention provides a process for the aluminothermic smelting of titanium-iron alloys based on composite aluminum materials, comprising the following steps:
[0008] S1. Preparation of composite aluminum scrap: S1.1 Pretreatment of aluminum scrap: The machined aluminum scrap is centrifuged to remove oil, dried, micro-etched with alkaline solution, washed and dried with water to obtain aluminum scrap; KH-570 is added to an ethanol-water mixed solution, the pH is adjusted with acetic acid, stirred and hydrolyzed, aluminum scrap is added, impregnated, filtered, and dried to obtain silanized aluminum scrap;
[0009] S1.2 Preparation of additives: PVA binder is added to fluoride-MgO composite, stirred evenly, placed in a fluidized bed, with modified Li2B4O7 as the core, atomized spraying, dried and cured, and sieved to obtain the additives;
[0010] S1.3 Aluminum Flake Modification: Mix the additives with PVA binder, stir evenly, place in a fluidized bed, spray evenly on the surface of silanized aluminum flakes, dry and cure to obtain composite aluminum flakes;
[0011] S2. Aluminum particle pretreatment: Aluminum particles are separated into fine-grained, medium-grained, and coarse-grained aluminum particles using a multi-layer vibrating screen.
[0012] S3. Preparation of titanium-iron alloy: S3.1 Gradient mixing: titanium concentrate and fine-grained aluminum particles are mixed evenly to obtain the bottom material; composite aluminum chips and medium-grained aluminum particles are mixed evenly to obtain the main reaction core material; coarse-grained aluminum particles are used as the high-temperature covering material;
[0013] S3.2 Layered material distribution: In the smelting furnace, first, the bottom layer material is evenly laid, scraped and compacted, with a thickness of 15~25mm. Then, the main reaction core material is laid on top, with a thickness of 80~120mm. Finally, the top is covered with a high-temperature covering material with a thickness of 20~35mm.
[0014] S3.3 Smelting: The high-temperature covering material is ignited with magnesium powder-potassium perchlorate igniter to initiate the aluminothermic reaction. After the reaction is complete, the material is calmed, the slag and metal are separated, and the mixture is cast to obtain a titanium-iron alloy.
[0015] The amount of the additive added is 5-12% of the mass of the aluminum scrap;
[0016] The additives include fluoride-MgO complex and modified Li2B4O7;
[0017] The modified Li2B4O7 is composed of Li2B4O7 glass phase, CaO and BaB6 micro powder through heat treatment; the fluoride-MgO composite is composed of Na3AlF6-CaF2 composite fluoride and nano MgO.
[0018] Furthermore, the preparation method of the modified Li2B4O7 includes the following steps:
[0019] S11. Mix Li2B4O7, CaO and BaB6, add anhydrous ethanol, ball mill and mix, then rotary evaporate and dry to obtain a mixed powder;
[0020] S12. The mixed powder is placed in a corundum crucible and heat-treated under the protection of high-purity argon. After cooling, it is ground and sieved to obtain modified Li2B4O7.
[0021] Furthermore, in the modified Li2B4O7, the mass percentages of Li2B4O7, CaO, and BaB6 micro powder are 10~13:6~9:1~2.
[0022] Furthermore, the preparation method of the fluoride-MgO complex includes the following steps:
[0023] S21. Mix Na3AlF6, CaF2 and AlF3, add anhydrous ethanol, and ball mill to mix, to obtain a composite fluoride;
[0024] S22. Disperse nano-MgO powder in anhydrous ethanol, add silane coupling agent KH-560, and ultrasonically disperse. Add the resulting suspension to the composite fluoride and stir evenly to obtain the composite fluoride-MgO complex.
[0025] Furthermore, the mass ratio of the modified Li2B4O7 to the fluoride-MgO complex is 1:3~5.
[0026] Furthermore, the aluminum particle size classification standard in S2 is 0.2~0.5mm as fine-grained aluminum particles, 0.5~1.0mm as medium-grained aluminum particles, and 1.0~3.0mm as coarse-grained aluminum particles, with an aluminum particle mass distribution ratio of 2.5:5.5:4.
[0027] Furthermore, in S3, the total aluminum demand is 30% of the titanium concentrate mass, and the total aluminum demand is the total amount of aluminum particles and composite aluminum chips, with the composite aluminum chips accounting for 40-60% of the total aluminum demand.
[0028] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:
[0029] 1. The fluoride-MgO complex preferentially melts in the initial stage of the reaction, forming a eutectic system with the complex fluoride. This allows the fluorination film-breaking reaction to begin at a lower temperature, and the fluoride decomposes to release a large amount of F. - Ions react with Al2O3 to undergo fluorination, dissolving and breaking down the alumina film while simultaneously forming a low-viscosity aluminum-oxygen-fluorine melt that promotes the diffusion of the film-breaking products. Nano-MgO reacts with Al2O3 to form the MgAl2O4 spinel phase, which expands in volume and cracks the oxide film from the inside, creating a dual physical-chemical film-breaking effect with the chemical dissolution of fluorides.
[0030] 2. During heat treatment, Li₂B₄O₇ encapsulates CaO and BaB₆ microparticles, not only integrating components with large density differences into uniformly dense composite particles, preventing stratification during storage and use, but also protecting the internal CaO and BaB₆ microparticles from oxidation or moisture absorption during storage. Simultaneously, during the reaction, Li₂B₄O₇ preferentially melts, gradually releasing the internal active components, achieving a staged reaction and extending the effective action time of the additives.
[0031] 3. Li released when Li₂B₄O₇ melts + Infiltration into the interstitial spaces of Al2O3 crystal lattice causes lattice distortion and stress concentration, which, along with the F in the complex fluoride-MgO complex, leads to... - Chemical etching from both inside and outside the film breaks down. BaB6 and F- The reaction gradually generates BF3 gas, which can penetrate the cracks in the ruptured oxide film and continue to deeply fluorinate and dissolve the inner layer of Al2O3 that has not been broken. CaO reacts with Li2B4O7 to form Ca3B2O6, which forms a low-viscosity melt at the reaction temperature. This melt is miscible with the outer fluoride melt, synergistically reducing the viscosity of the slag phase and improving slag-metal separation. Simultaneously, CaO has desulfurization capabilities and can react with acidic oxides such as SiO2 and P2O5, promoting the aggregation and flotation of inclusions, achieving melt purification, and improving titanium recovery rate and alloy purity. Attached Figure Description
[0032] Figure 1 This is a flowchart illustrating the preparation of the titanium-iron alloy in Example 1 of the present invention.
[0033] Figure 2 This is a physical image of the titanium-iron alloy prepared in Example 1 of the present invention. Detailed Implementation
[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0035] Example 1: This example discloses a process for smelting titanium-iron alloys using an aluminothermic method based on composite aluminum materials, including the following steps:
[0036] S1. Preparation of composite aluminum scrap: S1.1 Pretreatment of aluminum scrap: 20.1 kg of machined aluminum scrap was centrifuged to remove oil, dried at 120~150℃ for 2~4 h, micro-etched with 10% NaOH solution at 60~80℃ for 10 min, washed with deionized water, and dried at 80~100℃ for 2 h to obtain aluminum scrap; 200 g KH-570 was added to 44.4 L of ethanol-water mixed solution, the pH was adjusted to 4.5~5.5 with acetic acid, stirred and hydrolyzed for 30 min, 20 kg of aluminum scrap was added, impregnated for 30 min, filtered, and dried at 80℃ for 1 h to obtain silanized aluminum scrap;
[0037] S1.2 Preparation of additives: Add 5% PVA binder to 5kg fluoride-MgO composite, stir evenly, place in a fluidized bed, use 1kg modified Li2B4O7 as the core, atomize and spray at 80~120℃, dry and cure at 150~200℃ for 2~4h, and sieve to obtain the additives.
[0038] S1.3 Aluminum Flake Modification: Mix the additive with 2% PVA binder, stir evenly, place in a fluidized bed, spray evenly on the surface of silanized aluminum flakes, dry and cure at 110~130℃ for 1~2h to obtain composite aluminum flakes;
[0039] S2. Aluminum particle pretreatment: Aluminum particles are separated into fine-grained, medium-grained, and coarse-grained aluminum particles using a multi-layer vibrating screen.
[0040] S3. Preparation of titanium-iron alloy: (1) Gradient mixing: 100kg titanium concentrate and 2.5kg fine aluminum particles are mixed evenly to obtain the bottom material; 18kg composite aluminum chips and 5.5kg medium-sized aluminum particles are mixed evenly to obtain the main reaction core material; 4kg coarse aluminum particles are used as high-temperature covering material.
[0041] (2) Layered material distribution: In the smelting furnace, first, the bottom layer material is evenly laid, scraped and compacted, with a thickness of 15~25mm. Then, the main reaction core material is laid on top, with a thickness of 80~120mm. Finally, the top is covered with high-temperature covering material, with a thickness of 20~35mm.
[0042] (3) Smelting: The high-temperature covering material is ignited with magnesium powder-potassium perchlorate igniter to initiate the aluminothermic reaction. After the reaction is complete, the material is calmed, the slag and metal are separated, and the mixture is cast into a solid shape to obtain a titanium-iron alloy.
[0043] The amount of the additive added is 8% of the mass of the aluminum scrap;
[0044] The additives include fluoride-MgO complex and modified Li2B4O7;
[0045] The modified Li2B4O7 is composed of Li2B4O7 glass phase, CaO and BaB6 micro powder through heat treatment; the fluoride-MgO composite is composed of Na3AlF6-CaF2 composite fluoride and nano MgO.
[0046] It should be noted that the chemical composition of titanium concentrate is: TiO2 45~55%, FeO 20~30%, SiO2 5~10%, and other oxides 5~15%. For example... Figure 1 The diagram shown is a flowchart of the preparation process of titanium-iron alloy in Embodiment 1 of the present invention. The process adopts a gradient mixing and layered material distribution method. The top high-temperature covering material provides continuous high temperature and reducing atmosphere protection, the middle main reaction core material realizes the breaking of the alumina film and the reduction reaction, and the bottom bottom material ensures the reliable progress of the reaction.
[0047] The preparation method of the modified Li2B4O7 includes the following steps:
[0048] S11. Mix 13gLi2B4O7, 9gCaO and 2gBaB6, add 200mLan anhydrous ethanol, ball mill and mix for 5h, then dry by rotary evaporation at 60~70℃ to obtain mixed powder;
[0049] S12. The mixed powder is placed in a corundum crucible and heated to 820℃ at 5℃ / min under a high-purity argon atmosphere. The temperature is maintained for 1.5h to soften Li2B4O7 and coat other components. After cooling to room temperature, it is ground through a 100-mesh sieve to obtain modified Li2B4O7.
[0050] In the modified Li2B4O7, the mass percentages of Li2B4O7, CaO, and BaB6 micro powder are 13:9:2.
[0051] The preparation method of the fluoride-MgO complex includes the following steps:
[0052] S21. Mix 100g Na3AlF6, 40g CaF2 and 20g AlF3, add 200mL of anhydrous ethanol, and ball mill the mixture for 4h to obtain a composite fluoride.
[0053] S22. Disperse 10g of nano MgO powder in 100mL of anhydrous ethanol, add 0.2g of silane coupling agent KH-560, and ultrasonically disperse for 30min. Add the resulting suspension to the fluoride composite powder and stir evenly to obtain the composite fluoride-MgO complex.
[0054] The mass ratio of the modified Li2B4O7 to the fluoride-MgO complex is 1:5.
[0055] The particle size classification standard for aluminum particles in S2 is as follows: 0.2~0.5mm is fine-grained aluminum particles, 0.5~1.0mm is medium-grained aluminum particles, and 1.0~3.0mm is coarse-grained aluminum particles, with a particle mass distribution ratio of 2.5:5.5:4.
[0056] The total aluminum requirement in S3 is 30% of the titanium concentrate mass, and the total aluminum requirement is the total amount of aluminum granules and composite aluminum chips, with the composite aluminum chips accounting for 60% of the total aluminum requirement.
[0057] Example 2: This example is based on Example 1, but differs from Example 1 in that the amount of additive added in this example is 5% of the mass of aluminum scrap.
[0058] The other components and preparation methods are the same as in Example 1.
[0059] Example 3: This example is based on Example 1, but differs from Example 1 in that the amount of additive added in this example is 12% of the mass of aluminum scrap.
[0060] The other components and preparation methods are the same as in Example 1.
[0061] Example 4: This example is based on Example 1, but differs from Example 1 in that the mass percentage of Li2B4O7, CaO and BaB6 micro powder in the modified Li2B4O7 is 10:6:1.
[0062] The other components and preparation methods are the same as in Example 1.
[0063] Example 5: This example is based on Example 1, but differs from Example 1 in that the mass ratio of the modified Li2B4O7 to the fluoride-MgO complex is 1:3.
[0064] The other components and preparation methods are the same as in Example 1.
[0065] Example 6: The total aluminum requirement in S3 is 30% of the mass of titanium concentrate, the total aluminum requirement is the total amount of aluminum particles and composite aluminum chips, and the composite aluminum chips account for 40% of the total aluminum requirement.
[0066] The other components and preparation methods are the same as in Example 1.
[0067] Comparative Example 1: This comparative example is based on Example 1, but differs from Example 1 in that the fluoride-MgO composite described in this comparative example does not contain nano-MgO.
[0068] The other components and preparation methods are the same as in Example 1.
[0069] Comparative Example 2: This comparative example is based on Example 1, but differs from Example 1 in that the fluoride-MgO composite in this comparative example does not contain nano-magnesium oxide or Na3AlF6-CaF2 composite fluoride.
[0070] The other components and preparation methods are the same as in Example 1.
[0071] Comparative Example 3: This comparative example is based on Example 1, but differs from Example 1 in that the modified Li2B4O7 described in this comparative example is not subjected to high-temperature treatment.
[0072] The preparation method of the modified Li2B4O7 includes the following steps:
[0073] S11. Mix 13g Li2B4O7, 9g CaO and 2g BaB6, add 200mL anhydrous ethanol, ball mill and mix for 5h, dry by rotary evaporation at 60~70℃, and vacuum dry to obtain modified Li2B4O7.
[0074] The other components and preparation methods are the same as in Example 1.
[0075] Comparative Example 4: This comparative example is based on Example 1, but differs from Example 1 in that the modified Li2B4O7 described in this comparative example does not contain CaO.
[0076] The other components and preparation methods are the same as in Example 1.
[0077] Comparative Example 5: This comparative example is based on Example 1, but differs from Example 1 in that the modified Li2B4O7 described in this comparative example does not contain BaB6.
[0078] The other components and preparation methods are the same as in Example 1.
[0079] Comparative Example 6: This comparative example is based on Example 1, but differs from Example 1 in that the additive in this comparative example is a fluoride-MgO complex.
[0080] The other components and preparation methods are the same as in Example 1.
[0081] Comparative Example 7: This comparative example is based on Example 1, but differs from Example 1 in that the additive used in this comparative example is modified Li2B4O7.
[0082] The other components and preparation methods are the same as in Example 1.
[0083] Comparative Example 8: This comparative example is based on Example 1, but unlike Example 1, no additives are added to the composite aluminum chips in this comparative example.
[0084] The other components and preparation methods are the same as in Example 1.
[0085] Comparative Example 9: This comparative example is based on Example 1, but unlike Example 1, this comparative example does not add composite aluminum chips, and the total aluminum requirement is the total amount of aluminum particles.
[0086] Experimental verification:
[0087] Experiment 1:
[0088] (1) The composite aluminum chips prepared in Example 1 and Comparative Examples 1-8 were placed in a synchronous thermal analyzer and heated to 1200°C at a rate of 10°C / min in an air atmosphere with a flow rate of 50-100 mL / min. The DTA curve was analyzed to find the first significant exothermic peak onset temperature (Ton), which corresponds to the temperature point at which the aluminum oxide film on the surface of the aluminum chips is broken, and the fresh aluminum is rapidly oxidized or begins to react violently with the surrounding medium.
[0089] (2) The composite aluminum chips or pure aluminum particles prepared in Example 1 and Comparative Examples 1-9 were mixed evenly with copper oxide and placed in a corundum crucible. Under high-purity argon gas with a flow rate of 200 mL / min, the temperature was raised to 1100℃ at a rate of 10℃ / min and held for 30 minutes. After cooling, the mixture was removed and dilute nitric acid was added to dissolve the unreacted excess copper oxide and other soluble substances. The mixture was filtered and washed. The filter paper and filter residue were transferred into the crucible, dried, and ashed. The filter paper was then reduced at 500-600℃ for 30 minutes in a hydrogen atmosphere. After cooling, the mass of the obtained pure copper was accurately weighed and the effective aluminum content was calculated.
[0090] (3) Collect the slag produced after smelting in Examples 1 and Comparative Examples 1 to 8, crush it to <5mm, magnetically separate the magnetic metal particles, weigh and calculate the metal bead content, and analyze the proportion of aluminum-rich particles (unreacted aluminum) using ICP-OES.
[0091] Table 1. Verification of the efficacy of adjuvants:
[0092]
[0093] Table 1 shows the verification of the effect of the additive. By comparing Example 1 with the comparative example, it can be seen that the additive with a complete structure can effectively break the oxide film, significantly increase the effective aluminum content, reduce the film breaking temperature, significantly improve the reactivity of aluminum chips, and significantly reduce the aluminum content in the slag produced after smelting.
[0094] Experiment 2:
[0095] (1) Take representative chip samples from the final titanium-iron alloy, mix them evenly, dissolve them in acid, detect the Ti content using ICP-OES, and calculate the titanium recovery rate.
[0096] (2) Take representative chip samples from the final titanium-iron alloy, mix them evenly, dissolve them in acid, and use ICP-OES to detect the contents of Al, Si, O, N, S and C.
[0097] Table 2. Performance verification of titanium-iron alloy:
[0098]
[0099] Table 2 shows the performance verification of the titanium-iron alloy. Comparing Example 1 with Comparative Examples 8-9, the additive-modified composite aluminum chips showed comparable performance to pure aluminum granules, indicating that the additive-modified aluminum chips can replace part of the aluminum granule requirement. Furthermore, the additive modification significantly improves the problem of decreased titanium recovery rate caused by aluminum chips replacing aluminum granules. The final product is as follows... Figure 2 As shown, its impurity content conforms to the national standard for titanium-iron alloys.
[0100] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A process for aluminothermic smelting of titanium-iron alloys based on composite aluminum materials, characterized in that, Includes the following steps: S1. Preparation of composite aluminum scrap: S1.1 Pretreatment of aluminum scrap: The machined aluminum scrap is centrifuged to remove oil, dried, micro-etched with alkaline solution, washed and dried with water to obtain aluminum scrap; KH-570 is added to an ethanol-water mixed solution, the pH is adjusted with acetic acid, stirred and hydrolyzed, aluminum scrap is added, impregnated, filtered, and dried to obtain silanized aluminum scrap; S1.2 Preparation of additives: PVA binder is added to fluoride-MgO composite, stirred evenly, placed in a fluidized bed, with modified Li2B4O7 as the core, atomized spraying, dried and cured, and sieved to obtain the additives; S1.3 Aluminum Flake Modification: Mix the additives with PVA binder, stir evenly, place in a fluidized bed, spray evenly on the surface of silanized aluminum flakes, dry and cure to obtain composite aluminum flakes; S2. Aluminum particle pretreatment: Aluminum particles are separated into fine-grained, medium-grained, and coarse-grained aluminum particles using a multi-layer vibrating screen. S3. Preparation of titanium-iron alloy: S3.1 Gradient mixing: titanium concentrate and fine-grained aluminum particles are mixed evenly to obtain the bottom material; composite aluminum chips and medium-grained aluminum particles are mixed evenly to obtain the main reaction core material; coarse-grained aluminum particles are used as the high-temperature covering material; S3.2 Layered material distribution: In the smelting furnace, first, the bottom layer material is evenly laid, scraped and compacted, with a thickness of 15~25mm. Then, the main reaction core material is laid on top, with a thickness of 80~120mm. Finally, the top is covered with a high-temperature covering material with a thickness of 20~35mm. S3.3 Smelting: The high-temperature covering material is ignited with magnesium powder-potassium perchlorate igniter to initiate the aluminothermic reaction. After the reaction is complete, the material is calmed, the slag and metal are separated, and the mixture is cast to obtain a titanium-iron alloy. The amount of the additive added is 5-12% of the mass of the aluminum scrap; The additives include fluoride-MgO complex and modified Li2B4O7; The modified Li2B4O7 is composed of Li2B4O7 glass phase, CaO and BaB6 micro powder through heat treatment; the fluoride-MgO composite is composed of Na3AlF6-CaF2-AlF3 composite fluoride and nano MgO. The preparation method of the modified Li2B4O7 includes the following steps: S11. Mix Li2B4O7, CaO and BaB6, add anhydrous ethanol, ball mill and mix, then rotary evaporate and dry to obtain a mixed powder; S12. The mixed powder was placed in a corundum crucible and heated to 820℃ at 5℃ / min under the protection of high-purity argon. The mixture was held at this temperature for 1.5h for heat treatment. After cooling, it was ground and sieved to obtain modified Li2B4O7.
2. The process for aluminothermic smelting of titanium-iron alloy based on composite aluminum material according to claim 1, characterized in that, In the modified Li2B4O7, the mass percentages of Li2B4O7, CaO, and BaB6 micro powder are 10~13:6~9:1~2.
3. The process for aluminothermic smelting of titanium-iron alloy based on composite aluminum material according to claim 1, characterized in that, The preparation method of the composite fluoride-MgO complex includes the following steps: S21. Mix Na3AlF6, CaF2 and AlF3, add anhydrous ethanol, and ball mill to mix, to obtain a composite fluoride; S22. Disperse nano-MgO powder in anhydrous ethanol, add silane coupling agent KH-560, and ultrasonically disperse. Add the resulting suspension to the composite fluoride and stir evenly to obtain the composite fluoride-MgO complex.
4. The process for aluminothermic smelting of titanium-iron alloy based on composite aluminum material according to claim 1, characterized in that, The mass ratio of the modified Li2B4O7 to the fluoride-MgO complex is 1:3~5.
5. The process for aluminothermic smelting of titanium-iron alloy based on composite aluminum material according to claim 1, characterized in that, The particle size classification standard for aluminum particles in S2 is as follows: 0.2~0.5mm is fine-grained aluminum particles, 0.5~1.0mm is medium-grained aluminum particles, and 1.0~3.0mm is coarse-grained aluminum particles, with a particle mass distribution ratio of 2.5:5.5:
4.
6. The process for aluminothermic smelting of titanium-iron alloy based on composite aluminum material according to claim 1, characterized in that, The total aluminum requirement in S3 is 30% of the titanium concentrate mass, and the total aluminum requirement is the total amount of aluminum particles and composite aluminum chips, with the composite aluminum chips accounting for 40-60% of the total aluminum requirement.