A method for recycling cold-rolled scraps of TA10 titanium alloy

Abstract

The present invention discloses a method for recycling cold-rolled residues of TA10 titanium alloy, wherein the uncoiled raw materials sheared before welding the lead strip of the TA10 titanium alloy hot-rolled coil, the weld portion generated by the welding lead strip after cold rolling, the trimming generated during the finishing process, and the defective strips are collected, cleaned, and subjected to vacuum electromagnetic suspension melting to prepare a TA10 titanium alloy ingot. The prepared TA10 titanium alloy ingot is rolled to prepare a TA10 titanium alloy strip. On the one hand, since vacuum electromagnetic suspension melting has low requirements on the source, shape, and size of the cold-rolled residues, loading is convenient, thereby improving the recycling efficiency of the cold-rolled residues of the TA10 titanium alloy; on the other hand, since the cold-rolled residues of the TA10 titanium alloy have little contact with the crucible during the vacuum electromagnetic suspension melting process, the purity of the TA10 titanium alloy can be improved, and its toughness and corrosion resistance are not interfered with by impurities.

Description

Technical Field

[0001] The invention relates to the technical field of waste material recycling, and in particular to a method for recycling cold-rolled waste materials of a TA10 titanium alloy. Background Art

[0002] In the cold rolling process of TA10 titanium alloy strip, welding of the lead strip is required to complete key processes such as cold rolling, degreasing and annealing. Welding of the lead strip and subsequent finishing and slitting processes will produce a large amount of cold rolling residues.

[0003] In the existing technology, these cold-rolled scraps cannot be processed and modified, and can only be remelted using vacuum consumable arc melting (VAR) technology. On the one hand, since these cold-rolled scraps come from various sources and have large differences in shape and size, remelting and charging are difficult, and the recycling efficiency is low; on the other hand, since the prepared TA10 titanium alloy ingot is in contact with the crucible, the impurity content is high. In the subsequent rolling process, these impurities will cause the mechanical properties of the titanium strip to decrease, such as reducing the tensile strength, yield strength and elongation; affect the uniformity of the microstructure of the titanium strip, cause local organizational abnormalities, and thus reduce the overall performance stability of the material. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects in the prior art and provide a method for recovering cold-rolled residual material of TA10 titanium alloy.

[0005] To achieve the above object, the technical solution of the present invention is as follows: A method for recycling cold-rolled scraps of TA10 titanium alloy, comprising: The cold-rolled residues of TA10 titanium alloy are collected; the cold-rolled residues include the uncoiled raw materials of TA10 titanium alloy hot-rolled coils sheared before welding the lead strip, the length of the uncoiled raw materials is 30-50 mm, the weld part generated by the welding lead strip after cold rolling, the length of the weld part is 200-300 mm; the trimmings generated during the finishing process, and the defective strips; Cleaning the cold-rolled residue; Performing vacuum electromagnetic suspension melting on the cold-rolled residue to prepare a TA10 titanium alloy ingot; The TA10 titanium alloy ingot is rolled to prepare a TA10 titanium alloy strip.

[0006] According to the cold-rolled residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, the step of cleaning the cold-rolled residue comprises: sandblasting the cold-rolled residue, wherein the sandblasting medium is quartz sand or corundum sand.

[0007] According to the cold rolling residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, the sandblasting particle size is 20-200 mesh, the sandblasting pressure is 0.2-0.6MPa, the sandblasting angle is 30°-75°, and the sandblasting distance is 100-300mm.

[0008] According to the cold-rolled residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, the step of cleaning the cold-rolled residue comprises: chemically cleaning the cold-rolled residue with a cleaning agent; the cleaning agent comprises a surfactant cleaning agent, hydrochloric acid, a corrosion inhibitor and a chelating agent.

[0009] According to the cold-rolled residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, the cleaning temperature for chemical cleaning of the cold-rolled residue is 40-80° C., and the cleaning time is 10-20 min; mechanical stirring or ultrasonic stirring is used during the chemical cleaning process.

[0010] According to the cold-rolled residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, the step of cleaning the cold-rolled residue comprises: placing the cold-rolled residue in a vacuum heat treatment furnace for vacuum heat treatment, the heat treatment temperature is 500-600°C, the insulation time is 1-5h, and the vacuum degree is less than 0.1Pa.

[0011] According to the cold rolling residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, after the vacuum degree is less than 0.1Pa, argon gas is introduced into the vacuum heat treatment furnace to prevent oxidation of the cold rolling residue, and the purity of the argon gas is ≥99.99%.

[0012] According to the cold-rolled residue recycling method of TA10 titanium alloy provided in an embodiment of the present invention, the cold-rolled residue is subjected to vacuum electromagnetic suspension melting to prepare a TA10 titanium alloy ingot, comprising: cutting the cold-rolled residue into sheets with a thickness of 0.5-3 mm, a length of 20-40 mm, and a width of 20-40 mm, and placing the cold-rolled residue in a water-cooled crucible of a vacuum suspension melting furnace, and evacuating the water-cooled crucible to 6×10 -3 Pa, filling the water-cooled crucible with argon gas, the filling pressure of argon is 350-850Pa; the power in the insulation stage is 480KW-500KW, and the heating time is 15-20min, so that the alloying elements of the TA10 titanium alloy ingot are evenly mixed.

[0013] According to the cold rolling residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, the TA10 titanium alloy ingot is rolled to prepare a TA10 titanium alloy strip, comprising: heating the forged TA10 titanium alloy ingot to 950-1000°C in an electric heating furnace and then rough rolling to prepare a titanium strip blank; and fine rolling the titanium strip blank to prepare a TA10 titanium alloy strip with a thickness of 0.3-3mm.

[0014] According to the cold rolling residue recovery method of TA10 titanium alloy provided in an embodiment of the present invention, the forged TA10 titanium alloy ingot is heated to 950-1000°C in an electric heating furnace and then subjected to a rough rolling step, comprising: heating the forged TA10 titanium alloy ingot to 950-1000°C for a holding time of 0.5-1.5h; rolling the ingot through a four-roll reversible rolling mill at a rolling speed of 5.0-5.5m / s to prepare a titanium strip blank with a thickness of 35-45mm. The advantages and beneficial effects of the present invention are: The cold rolling residue recovery method of TA10 titanium alloy provided by the present invention collects, cleans and vacuum electromagnetic suspension melts the raw materials with a length of 30-50 mm before welding lead tape during the cold rolling, degreasing and annealing process of titanium alloy hot-rolled coil, the weld part of the welding lead tape with a length of 200-300 mm after welding lead tape, the trimming produced in the finishing process, and the defective strips to prepare TA10 titanium alloy ingots. The prepared TA10 titanium alloy ingots are rolled to prepare TA10 titanium alloy strips. On the one hand, since vacuum electromagnetic suspension melting has low requirements on the source, shape and size of cold rolling residues, loading is convenient, and the recycling efficiency of TA10 titanium alloy cold rolling residues is improved; on the other hand, since the TA10 titanium alloy cold rolling residues have little contact with the crucible during vacuum electromagnetic suspension melting, the purity of TA10 titanium alloy can be improved, so that its toughness and corrosion resistance are not interfered by impurities. Because the TA10 titanium alloy ingot achieves better composition uniformity and higher purity during the smelting process, the thickness accuracy and surface quality of the rolled titanium strip can be more accurately controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 1 is a schematic flow chart of a method for recovering cold-rolled residues of TA10 titanium alloy in an embodiment of the present invention; Figure 2 Schematic diagram of the change of melting current in vacuum electromagnetic suspension melting in an embodiment of the present invention; Figure 3 Schematic diagram of the change of melting current when the melt climbs the wall in vacuum electromagnetic suspension melting in an embodiment of the present invention; Figure 4 is a schematic structural diagram of a vacuum suspension melting furnace according to an embodiment of the present invention; Figure 5 It is a schematic diagram of welding a plurality of TA10 titanium alloy ingots into a consumable electrode in an embodiment of the present invention.

[0016] 1. TA10 titanium alloy ingot; 2. Consumable electrode; 3. Water-cooled crucible; 4. Induction coil. DETAILED DESCRIPTION

[0017] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0018] Figure 1 FIG. 1 is a schematic flow chart of a method for recovering cold-rolled residues of TA10 titanium alloy according to an embodiment of the present invention. Figure 1 As shown, the present invention provides a method for recovering cold-rolled residues of TA10 titanium alloy, comprising the following steps: S1: Collect the cold-rolled residues of TA10 titanium alloy; the cold-rolled residues include the uncoiled raw materials of TA10 titanium alloy hot-rolled coils sheared before welding the lead strip, the length of the uncoiled raw materials is 30-50mm, the weld part generated by the welding lead strip after cold rolling, the length of the weld part is 200-300mm, the trimming generated during the finishing process, and the defective strips; S2: Cleaning the cold-rolled residue; S3: vacuum electromagnetic suspension melting of the cold-rolled residue to prepare TA10 titanium alloy ingot; S4: rolling the TA10 titanium alloy ingot to prepare a TA10 titanium alloy strip.

[0019] The cold rolling residue recovery method of TA10 titanium alloy provided by the present invention collects, cleans and vacuum electromagnetic suspension melts the raw materials with a length of 30-50 mm before welding lead tape during the cold rolling, degreasing and annealing process of titanium alloy hot-rolled coil, the weld part of the welding lead tape with a length of 200-300 mm after welding lead tape, the trimming produced in the finishing process, and the defective strips to prepare TA10 titanium alloy ingots. The prepared TA10 titanium alloy ingots are rolled to prepare TA10 titanium alloy strips. On the one hand, since vacuum electromagnetic suspension melting has low requirements on the source, shape and size of cold rolling residues, loading is convenient, and the recycling efficiency of TA10 titanium alloy cold rolling residues is improved; on the other hand, since the TA10 titanium alloy cold rolling residues have little contact with the crucible during vacuum electromagnetic suspension melting, the purity of TA10 titanium alloy can be improved, so that its toughness and corrosion resistance are not interfered by impurities. Because the TA10 titanium alloy ingot achieves better composition uniformity and higher purity during the smelting process, the thickness accuracy and surface quality of the rolled titanium strip can be more accurately controlled.

[0020] It should be noted that the TA10 titanium alloy hot-rolled coil needs to be welded with a lead strip before cold rolling, degreasing and annealing in order to reduce the loss caused by the inability to roll the head and tail of the hot-rolled coil. Before welding the lead strip, it is necessary to cut the uncoiled raw material with a length of 30-50mm, a thickness of 2-3mm, and a width of 470-1550mm. After cold rolling, degreasing and annealing are completed, it is necessary to cut the weld part produced by the welding of the hot-rolled coil and the lead strip. In addition, during the finishing process, a trimming edge with a width of 20-30mm will be generated, as well as defective strips generated during the stripping process. These cold-rolled residues come from various sources, with large differences in shape and size, and can be efficiently recycled through vacuum electromagnetic suspension smelting.

[0021] In some embodiments, the step of cleaning the cold-rolled residues includes: using a grinding wheel or a sanding belt to grind the cold-rolled residues, the grinding pressure is 0.1MPa-0.3MPa, and the grinding speed is 15m / s-30m / s. Since the cold-rolled residues are large-area flat residues, grinding wheels or sanding belts are used for grinding. Since the grinding pressure is 0.1MPa-0.3MPa, it can not only ensure the effective removal of surface impurities, but also prevent the residues from being deformed or damaged; since the grinding speed is 15m / s-30m / s, it can avoid the surface burns or organizational structure changes of the residues due to excessively high temperatures, while ensuring the grinding efficiency. According to the surface condition of the cold-rolled residues, different directional strategies such as unidirectional grinding or cross grinding are adopted to obtain a more uniform and smooth surface quality. For example, rough grinding can be performed first to remove most impurities, and then fine grinding and precision grinding can be used to gradually improve the surface finish. After each grinding, the grinding debris remaining on the surface of the residual material should be cleaned in time to prevent it from having an adverse effect on subsequent grinding, so as to obtain residual materials with higher surface flatness requirements. By effectively removing surface impurities through grinding, the surface of the residual material is made smoother and brighter, which is conducive to the uniform diffusion and reaction of elements in the subsequent smelting process. In some embodiments, the step of cleaning the cold-rolled residue includes: sandblasting the cold-rolled residue, the sandblasting medium is quartz sand or corundum sand, the sandblasting particle size is 20-200 mesh, the sandblasting pressure is 0.2-0.6MPa, the sandblasting angle is 30°-75°, and the sandblasting distance is 100-300mm.

[0022] For removing oxides and light oil stains on the surface of cold-rolled residues, sandblasting media with moderate hardness such as quartz sand and corundum sand can be used. According to the surface roughness requirements of cold-rolled residues, select a sandblasting medium with a particle size of 20-200 mesh. The sandblasting pressure is between 0.2-0.6MPa, and is adjusted according to the material and surface condition of the residue. Too high pressure may cause excessive erosion of the surface of the residue, and too low pressure cannot effectively remove impurities. The sandblasting angle is controlled between 30°-75°, and can be optimized according to the shape of the residue and the area to be cleaned to ensure that the sandblasting flow can evenly impact the surface of the residue. The sandblasting distance is kept within the range of 100-300mm. Too close may cause local excessive sandblasting, and too far will reduce the sandblasting effect.

[0023] In some embodiments, the step of cleaning the cold-rolled residues includes: chemically cleaning the cold-rolled residues with a cleaning agent; the cleaning agent includes a surfactant cleaning agent, hydrochloric acid, a corrosion inhibitor and a chelating agent.

[0024] Since surfactant cleaning agents have good emulsification, dispersion and wetting properties, they can effectively reduce the adhesion between oil stains and the surface of the residue, making it easy to detach. It can be a non-ionic surfactant, such as fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, etc. Hydrochloric acid is used to remove oxides on the surface of cold-rolled residues. Add appropriate corrosion inhibitors to the cleaning solution. Corrosion inhibitors such as benzotriazole and sodium molybdate can prevent the cleaning agent from corroding the residue matrix. Chelating agents such as disodium ethylenediaminetetraacetic acid and citric acid can form stable complexes with metal ions on the surface of the residue, promote the dissolution and removal of metal impurities, and improve the cleaning efficiency. In addition, defoaming agents such as silicone defoaming agents can be added to reduce the generation of foam during the cleaning process and avoid the interference of foam on the cleaning effect and operation.

[0025] Adjust the formula of the cleaning agent according to the content and property changes of the pollutants on the surface of the cold-rolled residue to achieve the best cleaning effect. For example, when there is a lot of oil on the surface of the residue, appropriately increase the concentration of the surfactant; when the oxide content is high, reasonably increase the content of the acidic substance, but ensure that the synergy between the components is optimal to avoid affecting the overall cleaning effect due to excessive or low concentration of a certain component.

[0026] In some embodiments, the cleaning temperature for chemical cleaning of cold-rolled residues is 40-80°C, and the cleaning time is 10-20 minutes; mechanical stirring or ultrasonic stirring is used during the chemical cleaning process. The cleaning temperature needs to be precisely controlled according to the characteristics of the cleaning agent, the material of the residue and the type of pollutants to ensure that the adverse effects on the residue and the environment are minimized while effectively cleaning. When the cleaning temperature is 40-80°C, the movement speed of the cleaning agent molecules can be accelerated, and its chemical reaction rate and physical dissolution ability with pollutants can be enhanced, thereby improving the cleaning efficiency and avoiding problems such as excessively high temperature causing the cleaning agent to volatilize too quickly, aggravated corrosion of the residue matrix, and increased energy consumption.

[0027] Since the cold-rolled residues are slightly contaminated, a cleaning time of 10-20 minutes can achieve a satisfactory cleaning effect, preventing excessive corrosion or other adverse reactions on the surface of the residues caused by long-term immersion. In actual operation, the cleaning effect can be monitored in real time (such as observing the turbidity of the cleaning solution, the surface state of the residues, etc.), and the cleaning time can be dynamically adjusted to ensure the efficiency and economy of the cleaning process.

[0028] Mechanical stirring can generate convection in the cleaning liquid through rotating blades or stirring paddles, ensuring that all parts of the residual material surface are evenly washed. Ultrasonic stirring uses the cavitation effect of ultrasound to generate tiny bubbles in the cleaning liquid. The strong impact force generated when the bubbles burst effectively strips away the pollutants on the residual material surface. Ultrasonic equipment with a frequency of 20-40kHz and a power of 500-1000W can be used for stirring.

[0029] Finally, the cold-rolled residues are dried by hot air drying or vacuum drying. When hot air drying, the temperature is controlled at 60-80℃ and the wind speed is 3-5m / s. When vacuum drying, the vacuum degree is maintained at 0.05-0.08MPa, the temperature is 50-70℃, and the drying time is 20-60min. The dried cold-rolled residues should be stored in a dry and clean environment to avoid re-contamination.

[0030] In some embodiments, the step of cleaning the cold-rolled residues includes: placing the cold-rolled residues in a vacuum heat treatment furnace for vacuum heat treatment, the heat treatment temperature is 500-600°C, the holding time is 1-5h, and the vacuum degree is less than 0.1Pa. The cold-rolled residues are placed in a vacuum heat treatment furnace and evacuated to less than 0.1Pa to reduce the contact of the residues with gases such as oxygen and nitrogen during the heating process to prevent further oxidation and inhalation. According to the material of the residues and the surface contaminants, the heat treatment temperature is selected between 500-900°C. Within this temperature range, impurities such as oil stains and organic matter on the surface of the residues can be decomposed and volatilized in a vacuum environment, and gas impurities (such as hydrogen, oxygen, nitrogen, etc.) inside the residues can also escape, thereby effectively improving the surface quality of the residues. For example, for residues with a high hydrogen content, appropriately increasing the heat treatment temperature can promote the diffusion and escape of hydrogen.

[0031] Adjust the holding time between 1 and 5 hours according to the thickness of the cold-rolled residue and the batch holding time. Sufficient holding time can ensure that impurities are fully decomposed and gas impurities escape completely, but too long holding time may cause the grain growth of the residue and affect the material properties, which needs to be considered comprehensively. The surface of the residue after vacuum heat treatment is cleaner and smoother, and the internal structure is optimized, providing good raw material conditions for subsequent smelting and strip preparation.

[0032] In some embodiments, after the vacuum degree is less than 0.1Pa, argon is introduced into the vacuum heat treatment furnace to prevent oxidation of cold-rolled residues, and the purity of argon is ≥99.99%. For cold-rolled residues, high-purity argon (purity ≥99.99%) is often used as a protective atmosphere, which can effectively prevent the residue from oxidizing during the heating process. A small amount of hydrogen (such as 5%-10% H2 / Ar mixed gas) can also be added to the argon to use the reducing property of hydrogen to remove oxides on the surface of the residue. Figure 2 FIG. 1 is a schematic diagram of the variation of the melting current in vacuum electromagnetic levitation melting in an embodiment of the present invention. Figure 2 As shown, the steps of performing vacuum electromagnetic suspension melting on the cold-rolled residue to prepare a TA10 titanium alloy ingot include: cutting the cold-rolled residue into sheets with a thickness of 0.5-3 mm, a length of 20-40 mm, and a width of 20-40 mm, placing the cold-rolled residue in a water-cooled crucible of a vacuum suspension melting furnace, and evacuating the water-cooled crucible to 6×10 -3 Pa, fill the water-cooled crucible with argon gas at a pressure of 350-850Pa; the power in the insulation stage is 480KW-500KW, and the heating time is 15-20min, so that the alloy elements of the TA10 titanium alloy ingot are evenly mixed. Since the size of the sheet cold-rolled residue is 20-40mm, it is compatible with the charging space of the water-cooled crucible and ensures that the charging is dense.

[0033] The raw materials for smelting are melted once. At the beginning, the smelting current is 300A, which is maintained for 3 minutes; it is increased from 300A to 400A, which is maintained for 2 minutes; it is increased from 400A to 500A, which is maintained for 2 minutes; it is increased from 500A to 600A, which is maintained for 2 minutes; it is increased from 600A to 750A, which is maintained for 2 minutes; it is increased from 750A to 850A, which is maintained for 1 minute; it is increased from 850A to 950A, which is maintained for 30 seconds; it is increased from 950A to 1100A, which is maintained for 5 seconds; then it is kept warm for 5 minutes, and the smelting power is 480-500kw. The raw materials for smelting are completely melted, and then the power is reduced to the minimum (80kw) within 10 seconds, and the power is turned off. The primary ingot is cooled in a water-cooled crucible for 1.5 hours and then taken out of the furnace to prepare the primary ingot. The primary ingot is reversed and smelted twice. The smelting current setting value and cooling time are the same as those of the primary smelting to prepare the secondary ingot. The secondary ingot is reversed and smelted for the third time, with the smelting current setting value and cooling time being the same as those for the first smelting.

[0034] Figure 4 Schematic diagram of the structure of the vacuum suspension melting furnace in the embodiment of the present invention. Figure 4 As shown, after the smelting starts, the smelting current and smelting voltage are passed through the induction coil, and the cold-rolled residue inside the water-cooled crucible begins to melt. When the smelting is completed, the heating power is reduced from 500KW to 80KW within 10-20S, and then the power is turned off to avoid the ingot and the crucible from sticking together due to the power reduction rate being too fast or too slow. During the ingot removal process, two people cooperate, one operates the hydraulic pressure, and the other uses a basin under the water-cooled crucible to receive the ingot.

[0035] In the vacuum electromagnetic suspension melting process, the flaky waste material has a relatively large heating area and good melting uniformity, which helps to reduce local overheating or overcooling and reduces the risk of component segregation caused by uneven temperature. The suspension stability is relatively good, which improves the controllability of the melting process, reduces the possibility of contact with the crucible wall, and ensures the purity of the melting process.

[0036] It should be noted that vacuum electromagnetic levitation melting of TA10 titanium alloy has many advantages, specifically: Purity improvement: In the case of containerless smelting, the pollution of the alloy by container materials such as crucibles is reduced. For example, the traditional smelting method may cause impurity elements in the crucible material to mix into the alloy, while suspension smelting can avoid this situation, ensuring the high purity of TA10 titanium alloy and making its corrosion resistance not interfered by impurities.

[0037] Good composition uniformity: During the suspension smelting process, the alloy melt is evenly heated in a suspended state, which is conducive to the uniform distribution of alloy elements. For TA10 titanium alloy, alloy elements such as molybdenum and nickel can be better dispersed in the titanium matrix, avoiding composition segregation, making the performance of the alloy more stable and consistent.

[0038] Good refining effect: Suspension melting in a vacuum environment can effectively remove gas impurities in the alloy. For example, hydrogen, oxygen, etc. If the content of these gas impurities is too high, it will reduce the quality of TA10 titanium alloy, especially its toughness and corrosion resistance. Through the refining effect of suspension melting, the content of these gas impurities can be reduced and the quality of the alloy can be improved.

[0039] It should also be noted that the use of sheet-shaped cold-rolled residues has many advantages, specifically: Large heating area: Flake waste has a large surface area to volume ratio, and its heating area is relatively large during vacuum electromagnetic suspension melting. For example, flake material with a thickness of 3-5mm and a length and width of 20-40mm can absorb heat more quickly under the action of the electromagnetic field, thereby reaching the melting point and melting faster.

[0040] Good melting uniformity: Since the heat can be evenly distributed over the entire sheet surface, the melting process is relatively uniform. This helps to reduce local overheating or overcooling, so that the alloy components can be better mixed at the beginning of melting, which is beneficial to the subsequent component homogenization process.

[0041] High suspension stability: The flaky waste has relatively good suspension stability in the electromagnetic field. Due to its relatively flat shape, it can be suspended relatively stably in the crucible under the action of electromagnetic force, reducing the possibility of contact with the crucible wall and the risk of crucible contamination.

[0042] Good force uniformity: The force distribution of the electromagnetic field on the flaky waste is relatively uniform, making it difficult for the waste to roll or deflect during the suspension process, which is conducive to maintaining a stable melting state and improving the controllability of the melting process.

[0043] Rapid element diffusion: After melting, the elements in the melt formed by the flake scrap diffuse rapidly. Due to its large surface area, the contact area between the elements is large, which promotes the rapid diffusion and uniform mixing of the elements, and helps to obtain a uniform alloy melt in a shorter time.

[0044] High melting efficiency: Due to the rapid melting and good composition homogenization characteristics of flake scrap, its overall melting efficiency is relatively high. Under the same process conditions, flake scrap can complete the melting process faster, reducing the production cycle and improving the production capacity of the equipment.

[0045] Relatively low energy consumption: Faster melting speed means that relatively less energy is consumed per unit time, thus reducing the energy consumption of the melting process. For example, when achieving the same melting degree and composition uniformity requirements, the total energy input required for flake scrap may be 10-20% less than that for lump scrap.

[0046] Melting in a protective gas atmosphere with a pressure of 350-850Pa can squeeze out possible active gases, further reduce the risk of metal oxidation or nitridation, and improve the purity of the alloy. The presence of argon can also make the melting environment more stable. In the vacuum magnetic levitation melting process, the metal raw materials are suspended and heated to melt under the action of electromagnetic force. Argon can act as a buffer to reduce the splashing and volatilization of the melt. For example, when the melt may have some fluctuations or tiny splashing at high temperatures, argon can suppress this situation, making the melting process more stable and helping to accurately control melting parameters such as temperature and melting time.

[0047] As a gas medium, argon can affect the transfer of heat to a certain extent. During the smelting process, it can help evenly distribute heat and make the metal raw materials heated more evenly. For vacuum magnetic levitation melting, a process that requires precise temperature control, this characteristic of argon helps ensure that all parts of the metal raw materials can reach the appropriate melting temperature, thereby promoting the homogenization of alloy components and reducing the phenomenon of component segregation.

[0048] According to the characteristics of TA10 titanium alloy, the heating power and heating time are adjusted to control the melting temperature at 1650-1950°C. By slowly increasing the melting power, it is ensured that the raw materials are fully melted and the composition is uniform, and internal stress or local overheating of the material caused by too fast heating is avoided, which affects the quality of the ingot. In some embodiments, after the melting is completed, the heat is kept for 5 minutes, and then the melting power is reduced and the power is turned off for cooling. This precisely controlled heating, insulation and cooling process helps to further optimize the organizational structure and composition uniformity of the ingot and improve the quality of the ingot.

[0049] In some embodiments, the melt is strongly stirred under the action of electromagnetic force to improve the composition uniformity of the TA10 titanium alloy ingot. Specifically, at a frequency of 10 kHz, as the current increases from 300 A to 1100 A, the flow velocity of the melt increases, and the flow pattern and vortex position remain unchanged, but the flow velocity is accelerated. Therefore, the stirring effect of the melt can be enhanced by increasing the current.

[0050] Figure 3 FIG. 1 is a schematic diagram of the variation of the melting current when the melt climbs the wall in vacuum electromagnetic suspension melting in an embodiment of the present invention. Figure 3As shown, in order to ensure that the alloy ingot is melted under effective support, the power is adjusted according to the state of the molten pool. That is, when the alloy ingot begins to sink, the power is increased in time to ensure that the alloy ingot is melted under effective magnetic support to prevent the unmelted ingot from sinking quickly to the bottom of the crucible. During the melting process, if the molten metal climbs the wall of the water-cooled crucible, the temperature is raised for the second time. Specifically, the heating power is reduced from 480KW-500KW (current 1100A) to 700-900A, maintained for 5-8S, and then increased to 480KW-500KW again.

[0051] In some embodiments, the step of performing vacuum electromagnetic suspension melting on the residual waste material and the alloy raw material further includes: The scrap material and alloy raw material are melted once, with a cooling time of 90min-120min, to prepare a primary ingot; the primary ingot is reversed and melted twice, with the melting parameters being the same as the primary melting, to prepare a secondary ingot; the secondary ingot is reversed and melted three times, with the melting parameters being the same as the primary melting, to prepare a TA10 titanium alloy ingot.

[0052] Figure 5 Schematic diagram of welding a plurality of TA10 titanium alloy ingots into a consumable electrode in an embodiment of the present invention, such as Figure 5 As shown, in some embodiments, multiple TA10 titanium alloy ingots are welded together by an electron beam welding box to prepare consumable electrodes, and the consumable electrodes are melted by a vacuum consumable arc to prepare large-sized TA10 titanium alloy ingots to improve production efficiency. The number of welded TA10 titanium alloy ingots can be flexibly adjusted according to actual needs to meet the diversified requirements of rolling.

[0053] When welding is performed by an electron beam welding box, the welding current is 1-3A, the welding voltage is 30KV, and the welding speed is 20-50mm / min. When using an electron beam welding box for welding, due to the very high energy density of the electron beam, the electron beam can be focused to a very small diameter. This high energy density can achieve high-precision welding, which can make the weld very narrow and have a large aspect ratio, which helps to improve production efficiency and greatly shorten the welding time. The width of the annular weld is 80-100mm and the depth is 30-50mm. Since the other parts of the TA10 titanium alloy ingot are less affected by heat during the welding process, thermal deformation and thermal stress can be reduced, and cracks in the annular weld due to thermal stress after welding can be prevented.

[0054] In some embodiments, the step of rolling the TA10 titanium alloy ingot to prepare a TA10 titanium alloy strip comprises: heating the forged TA10 titanium alloy ingot to 950-1000°C in an electric heating furnace and then rough rolling the titanium strip to prepare a titanium strip blank; and fine rolling the titanium strip blank to prepare a TA10 titanium alloy strip with a thickness of 0.3-3 mm.

[0055] In some embodiments, the forged TA10 titanium alloy ingot is heated to 950-1000° C. in an electric heating furnace and then subjected to a rough rolling step, comprising: heating the forged TA10 titanium alloy ingot to 950-1000° C. for a holding time of 0.5-1.5 h; rolling the ingot through a four-roll reversible rolling mill at a rolling speed of 5.0-5.5 m / s to prepare a titanium strip blank with a thickness of 35-45 mm. In some embodiments, the step of fine rolling the titanium strip blank comprises: The titanium strip is subjected to uniform temperature treatment by a hot coil box or a heating furnace so that the temperature fluctuation range is ±20°C during the precision rolling of the titanium strip; the titanium strip is subjected to precision rolling by a six-roll or twenty-roll rolling mill with a rolling speed of 10-20m / s and a working roll diameter of 300-500mm to prepare TA10 titanium alloy strip with a thickness of 0.3~3mm.

[0056] Before finishing rolling, the titanium strip is kept warm and treated with even temperature treatment. Hot coil boxes or heating furnaces can be used to ensure that the temperature of the strip is uniform when it enters finishing rolling, thereby reducing the problems of plate shape and size deviation caused by uneven temperature.

[0057] In some embodiments, before the step of fine rolling the titanium strip blank, the method further comprises: 8-12 pieces of strip steel are rolled through a six-roll or twenty-roll mill to form an oxide film on the surface of the working roll. By first rolling 8-12 pieces of strip steel to form a stable oxide film on the surface of the working roll, the friction coefficient during the rolling process is reduced and the surface quality of the strip is improved.

[0058] In some embodiments, after the step of hot rolling the rolled slab, the method further comprises: The hot-rolled titanium strip is cold-rolled at a rolling speed of 5-15 m / s and a tension of 50-150 MPa to prepare a TA10 titanium alloy strip with a thickness of 0.1-0.3 mm; After rolling, the TA10 titanium alloy strip is annealed at a temperature of 600-700°C and a holding time of 1-3h.

[0059] If the product has high requirements for thickness accuracy and surface quality, cold rolling can be performed after hot rolling. Before cold rolling, the hot-rolled strip is subjected to surface treatments such as degreasing and pickling to remove surface oil and scale. A six-roll or twenty-roll cold rolling mill is used, and the cold rolling reduction is set according to the final thickness requirements of the product. During the cold rolling process, the rolling speed is controlled to be 5-15m / s and the tension is 50-150MPa to ensure the flatness and thickness accuracy of the strip.

[0060] After rolling, the TA10 titanium alloy strip is annealed to eliminate work hardening and improve the structure and performance. According to the thickness and performance requirements of the strip, a suitable annealing method is selected, such as continuous annealing or hood annealing. The annealed strip is surface treated, such as alkali pickling, sanding, polishing, etc., to remove surface oxide scale, impurities and minor defects, and improve the surface finish and flatness of the strip.

[0061] A specific embodiment of the cold rolling residue recovery method of TA10 titanium alloy of the present invention is described below: The cold-rolled residues of TA10 titanium alloy are collected; the cold-rolled residues include the uncoiled raw materials of TA10 titanium alloy hot-rolled coils sheared before welding the lead strips, the uncoiled raw materials are 30-50 mm long, the weld portions generated by welding the lead strips after cold rolling, the weld portions are 200-300 mm long, the trimmings generated during the finishing process, and defective strips.

[0062] The cold-rolled residue is chemically cleaned by a cleaning agent; the cleaning agent includes a surfactant cleaning agent, hydrochloric acid, a corrosion inhibitor and a chelating agent. The cleaning temperature for chemical cleaning of the cold-rolled residue is 40-80°C, and the cleaning time is 10-20 minutes; mechanical stirring or ultrasonic stirring is used during the chemical cleaning process. And / or the cold-rolled residue is placed in a vacuum heat treatment furnace for vacuum heat treatment, the heat treatment temperature is 500-600°C, the insulation time is 1-5 hours, and the vacuum degree is less than 0.1Pa.

[0063] The cold-rolled residue was melted once, and the water-cooled crucible of the vacuum suspension melting furnace was evacuated to 6×10 -3 Pa, fill the water-cooled crucible with argon gas, and the argon filling pressure is 350-850Pa; the power in the insulation stage is 480KW-500KW, and the heating time is 15-20min, so that the alloy elements of the TA10 titanium alloy ingot are evenly mixed. The primary ingot is cooled in the water-cooled crucible for 1.5h and then taken out of the furnace to prepare the primary ingot. The primary ingot is reversed and smelted for the second time, with the same smelting parameters as the primary smelting, to prepare the secondary ingot; the secondary ingot is reversed and smelted for the third time, with the same smelting parameters as the primary smelting, to prepare the TA10 titanium alloy ingot. The ingot specification is 220mm in diameter and 100kg in feed.

[0064] The forged TA10 titanium alloy ingot is heated to 950-1000°C for a holding time of 0.5-1.5h; and rolled by a four-roll reversible rolling mill with a rolling speed set at 5.0-5.5m / s to prepare a titanium strip with a thickness of 35-45mm.

[0065] The titanium strip is subjected to uniform temperature treatment through a hot coil box or a heating furnace, so that the temperature fluctuation range is ±20°C during the precision rolling of the titanium strip; the titanium strip is subjected to precision rolling through a six-roll or twenty-roll rolling mill, the rolling speed is 10-20m / s, and the working roll diameter is 300-500mm.

[0066] The hot-rolled titanium strip is cold rolled at a rolling speed of 5-15 m / s and a tension of 50-150 MPa to prepare a TA10 titanium alloy strip with a thickness of 0.1-0.3 mm. After rolling, the TA10 titanium alloy strip is annealed at a temperature of 600-700°C and a holding time of 1-3 hours.

[0067] The dimensional accuracy of the TA10 titanium alloy strip prepared by the above-mentioned TA10 titanium alloy cold rolling waste recovery method is significantly improved, the thickness deviation is controlled within ±0.03mm, the width deviation is controlled within ±3mm, the surface quality is greatly improved, the surface finish is high, and there are no obvious defects.

[0068] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for recovering cold-rolled residues of TA10 titanium alloy, characterized in that: include: The cold-rolled residues of TA10 titanium alloy are collected; the cold-rolled residues include the uncoiled raw materials of TA10 titanium alloy hot-rolled coils sheared before welding the lead strip, the length of the uncoiled raw materials is 30-50 mm, the weld part generated by the welding lead strip after cold rolling, the length of the weld part is 200-300 mm; the trimmings generated during the finishing process, and the defective strips; Cleaning the cold-rolled residue; Performing vacuum electromagnetic suspension melting on the cold-rolled residue to prepare a TA10 titanium alloy ingot; The TA10 titanium alloy ingot is rolled to prepare a TA10 titanium alloy strip.

2. The cold rolling residue recovery method of TA10 titanium alloy according to claim 1, characterized in that: The step of cleaning the cold-rolled residue comprises: sandblasting the cold-rolled residue, wherein the sandblasting medium is quartz sand or corundum sand.

3. The cold rolling residue recovery method of TA10 titanium alloy according to claim 2, characterized in that: The sandblasting particle size is 20-200 mesh, the sandblasting pressure is 0.2-0.6MPa, the sandblasting angle is 30°-75°, and the sandblasting distance is 100-300mm.

4. The cold rolling residue recovery method of TA10 titanium alloy according to claim 1, characterized in that: The step of cleaning the cold-rolled residues comprises: chemically cleaning the cold-rolled residues by a cleaning agent; the cleaning agent comprises a surfactant cleaning agent, hydrochloric acid, a corrosion inhibitor and a chelating agent.

5. The cold rolling residue recovery method of TA10 titanium alloy according to claim 4, characterized in that: The cleaning temperature for chemical cleaning of the cold-rolled residue is 40-80° C., and the cleaning time is 10-20 minutes. Mechanical stirring or ultrasonic stirring is used during the chemical cleaning process.

6. The cold rolling residue recovery method of TA10 titanium alloy according to claim 1, characterized in that: The step of cleaning the cold-rolled residues comprises: placing the cold-rolled residues in a vacuum heat treatment furnace for vacuum heat treatment, the heat treatment temperature is 500-600°C, the insulation time is 1-5h, and the vacuum degree is less than 0.1Pa.

7. The cold rolling residue recovery method of TA10 titanium alloy according to claim 6, characterized in that: After the vacuum degree is less than 0.1 Pa, argon gas is introduced into the vacuum heat treatment furnace to prevent oxidation of the cold-rolled residue, and the purity of the argon gas is ≥99.99%.

8. The cold rolling residue recovery method of TA10 titanium alloy according to any one of claims 1 to 7, characterized in that: The step of performing vacuum electromagnetic suspension melting on the cold-rolled residue to prepare a TA10 titanium alloy ingot comprises: cutting the cold-rolled residue into sheets with a thickness of 0.5-3 mm, a length of 20-40 mm, and a width of 20-40 mm, placing the cold-rolled residue in a water-cooled crucible of a vacuum suspension melting furnace, and evacuating the water-cooled crucible to 6×10 -3 Pa, filling the water-cooled crucible with argon gas, the filling pressure of argon is 350-850Pa; the power in the insulation stage is 480KW-500KW, and the heating time is 15-20min, so that the alloying elements of the TA10 titanium alloy ingot are evenly mixed.

9. The cold rolling residue recovery method of TA10 titanium alloy according to any one of claims 1 to 7, characterized in that: The step of rolling the TA10 titanium alloy ingot to prepare a TA10 titanium alloy strip comprises: heating the forged TA10 titanium alloy ingot to 950-1000° C. in an electric heating furnace and then performing rough rolling to prepare a titanium strip blank; and fine rolling the titanium strip blank to prepare a TA10 titanium alloy strip with a thickness of 0.3-3 mm.

10. The cold rolling residue recovery method of TA10 titanium alloy according to claim 9, characterized in that: The forged TA10 titanium alloy ingot is heated to 950-1000°C in an electric heating furnace and then subjected to a rough rolling step, comprising: heating the forged TA10 titanium alloy ingot to 950-1000°C for a holding time of 0.5-1.5h; and rolling the ingot through a four-roll reversible rolling mill with a rolling speed set to 5.0-5.5m / s to prepare the titanium strip blank with a thickness of 35-45mm.

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