A method for preparing TA10 strip

Abstract

The present invention discloses a method for preparing a TA10 strip, wherein TA10 titanium alloy ingots are prepared by vacuum electromagnetic suspension melting of flaky titanium and titanium alloy waste materials and alloy raw materials. The ingots are then forged and hot rolled to prepare TA10 titanium alloy strips. On the one hand, the flaky titanium and titanium alloy waste materials are melted by vacuum electromagnetic suspension melting, so that the waste materials can be recycled; on the other hand, the waste materials have fewer impurities than sponge titanium, which can improve the purity of the ingots and make their toughness and corrosion resistance not interfered by impurities. In addition, during the vacuum electromagnetic suspension melting process, the flaky waste materials have 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. Since the ingots achieve better component uniformity and higher purity during the melting process, the thickness accuracy and surface quality of the rolled titanium strip can be more accurately controlled.

Description

Technical Field

[0001] The invention relates to the technical field of titanium material processing, and in particular to a method for preparing a TA10 strip. Background Art

[0002] TA10 titanium alloy strip has shown extensive and important application value in many fields due to its excellent comprehensive performance. In the chemical industry, TA10 titanium alloy strip is widely used in the manufacture of various corrosion-resistant equipment. In the field of marine engineering, TA10 titanium alloy strip is used in offshore platforms, seawater desalination equipment, shipbuilding, etc. In addition, in high-end fields such as aerospace, medical equipment, and the electric power industry, TA10 titanium alloy strip also plays an indispensable role due to its good mechanical properties, organizational stability and machinability. With the continuous development of modern industry, the demand for TA10 titanium alloy strip continues to grow, and higher and higher requirements are also placed on its quality and performance.

[0003] The existing technology uses vacuum consumable arc melting (VAR) technology to prepare TA10 ingots, which are then rolled into titanium strips. During the smelting process, the TA10 ingots prepared by the VAR process have a high impurity content, which mainly comes from impurities in the raw materials, erosion of the crucible material during the smelting process, and gas ionization products during the arc discharge process. In the subsequent rolling process, these impurities will cause the mechanical properties of the titanium strip to decrease, such as reducing tensile strength, yield strength and elongation; affect the uniformity of the microstructure of the titanium strip, cause local tissue abnormalities, and thus reduce the overall performance stability of the material. In addition, impurities will also have an adverse effect on the surface quality of the titanium strip, resulting in surface defects such as cracks and pits, reducing the product yield and performance. 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 preparing TA10 strip.

[0005] To achieve the above object, the technical solution of the present invention is as follows: A method for preparing TA10 strip comprises the following steps: Cleaning the scraps of titanium and titanium alloys, wherein the scraps are in the form of flakes; Placing the residual waste material and the alloy raw material in a water-cooled crucible of a vacuum electromagnetic suspension furnace according to the target composition range of the TA10 titanium alloy ingot, and performing vacuum electromagnetic suspension melting on the residual waste material and the alloy raw material to prepare the TA10 titanium alloy ingot; Forging the TA10 titanium alloy ingot to prepare a rolled slab; The rolled slab is hot rolled to prepare a TA10 titanium alloy strip.

[0006] According to the method for preparing TA10 strip provided by an embodiment of the present invention, the scrap material has a thickness of 3-5 mm, a length of 20-30 mm, and a width of 20-30 mm; the grade of the scrap material is industrial pure titanium or TA10.

[0007] According to the method for preparing TA10 strip provided by an embodiment of the present invention, the step of cleaning the residual waste of titanium and titanium alloy comprises: Cutting the scrap plate of titanium and titanium alloy so that the scrap plate meets the size requirements; Acid washing and / or alkali washing are performed according to the surface condition of the residual waste material; when acid washing is performed, the acid washing solution contains 10-15% by volume of hydrochloric acid and 0.5-1% by volume of a corrosion inhibitor, the acid washing temperature is 30-40°C, and the acid washing time is 10-20min; when alkali washing is performed, the alkali washing solution contains 5-10g / L of sodium hydroxide, 20-30g / L of sodium carbonate, and 10-15g / L of sodium phosphate, the alkali washing temperature is 50-70°C, and the alkali washing time is 15-30min; The ultrasonic cleaning equipment with a frequency of 20-40kHz and a power of 500-1000W is used to perform ultrasonic cleaning on the residual waste material after acid washing and / or alkali washing, and the cleaning liquid is deionized water or distilled water.

[0008] According to the method for preparing TA10 strip provided by an embodiment of the present invention, the step of performing vacuum electromagnetic suspension melting on the scrap material and the alloy raw material comprises: 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 filling pressure 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.

[0009] According to the method for preparing TA10 strip provided by an embodiment of the present invention, the step of performing vacuum electromagnetic suspension melting on the scrap material and the alloy raw material further includes: The scrap material and the alloy raw material are melted once, with a cooling time of 90 min-120 min, to prepare a primary ingot; the primary ingot is reversed and melted twice, with the melting parameters being the same as those of 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 those of the primary melting, to prepare a TA10 titanium alloy ingot.

[0010] According to the method for preparing TA10 strip provided by an embodiment of the present invention, the step of hot rolling the rolled slab comprises: The forged TA10 titanium alloy ingot is heated to 950-1000° C. in an electric heating furnace and then roughly rolled to prepare a titanium strip blank; The titanium strip blank is subjected to precision rolling to prepare a TA10 titanium alloy strip with a thickness of 0.3-3 mm.

[0011] According to the method for preparing TA10 strip provided in an embodiment of the present invention, the step of heating the forged TA10 ingot to 950-1000° C. in an electric heating furnace and then performing rough rolling comprises: The forged TA10 titanium alloy ingot is heated to 950-1000° C. for a holding time of 0.5-1.5 h; and rolled by a four-roll reversible rolling mill with a rolling speed set at 5.0-5.5 m / s to prepare the titanium strip blank with a thickness of 35-45 mm.

[0012] According to the method for preparing TA10 strip provided by an embodiment of the present invention, 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 of the titanium strip 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.

[0013] According to the method for preparing TA10 strip provided by an embodiment of the present invention, before the step of fine rolling the titanium strip blank, the method further comprises: 8-12 pieces of steel strips are rolled through a six-roll or twenty-roll mill so that an oxide film is formed on the surface of the working rolls.

[0014] The method for preparing the TA10 strip provided in an embodiment of the present invention further comprises, after the step of hot rolling the rolled slab: Cold rolling the hot-rolled titanium strip blank at a rolling speed of 5-15 m / s and a tension of 50-150 MPa to prepare the 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.

[0015] The advantages and beneficial effects of the present invention are: The preparation method of TA10 strip provided by the present invention is to prepare TA10 titanium alloy ingots by vacuum electromagnetic suspension melting of flaky titanium and titanium alloy waste materials and alloy raw materials. Then the TA10 titanium alloy ingots are forged and hot rolled to prepare TA10 titanium alloy strips. On the one hand, the flaky titanium and titanium alloy waste materials are melted by vacuum electromagnetic suspension to achieve the recycling of the waste materials; on the other hand, the waste materials have fewer impurities than sponge titanium, which can improve the purity of TA10 titanium alloy and make its toughness and corrosion resistance not interfered by impurities. In addition, in the process of vacuum electromagnetic suspension melting, the heating area of ​​the flaky waste materials is relatively large, and the melting uniformity is good, which helps to reduce local overheating or supercooling, 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. 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

[0016] Figure 1 1 is a schematic diagram of a process for preparing a TA10 strip according to 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.

[0017] 1. TA10 titanium alloy ingot; 2. Consumable electrode; 3. Water-cooled crucible; 4. Induction coil. DETAILED DESCRIPTION

[0018] 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.

[0019] Figure 1 Schematic diagram of the process of preparing TA10 strip in an embodiment of the present invention. Figure 1 As shown, the present invention provides a method for preparing a TA10 strip, comprising the following steps: S1: Cleaning the scraps of titanium and titanium alloys, the scraps are in the form of flakes; S2: placing the waste material and the alloy raw material in a water-cooled crucible of a vacuum electromagnetic suspension furnace according to the target composition range of the TA10 titanium alloy ingot, and performing vacuum electromagnetic suspension melting on the waste material and the alloy raw material to prepare a TA10 titanium alloy ingot; S3: forging the TA10 titanium alloy ingot to prepare a rolled slab; S4: hot rolling the rolled slab to prepare a TA10 titanium alloy strip.

[0020] The preparation method of TA10 strip provided by the present invention is to prepare TA10 titanium alloy ingots by vacuum electromagnetic suspension melting of flaky titanium and titanium alloy waste materials and alloy raw materials. Then the TA10 titanium alloy ingots are forged and hot rolled to prepare TA10 titanium alloy strips. On the one hand, the flaky titanium and titanium alloy waste materials are melted by vacuum electromagnetic suspension to achieve the recycling of the waste materials; on the other hand, the waste materials have fewer impurities than sponge titanium, which can improve the purity of TA10 titanium alloy and make its toughness and corrosion resistance not interfered by impurities. In addition, in the process of vacuum electromagnetic suspension melting, the heating area of ​​the flaky waste materials is relatively large, and the melting uniformity is good, which helps to reduce local overheating or supercooling, 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. 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] It should also be noted that the use of flake titanium and titanium alloy scrap 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 20-30mm can absorb heat more quickly under the action of the electromagnetic field, thereby reaching the melting point and melting faster.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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 5As shown, in some embodiments, after the step of vacuum electromagnetic suspension melting of the residual waste and alloy raw materials, it also includes: welding a plurality of TA10 titanium alloy ingots by an electron beam welding box to prepare consumable electrodes, and melting the consumable electrodes by 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.

[0032] 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.

[0033] In some embodiments, the scrap material has a thickness of 3-5 mm, a length of 20-30 mm, and a width of 20-30 mm; the grade of the scrap material is industrial pure titanium or TA10.

[0034] Scrap can be the leftovers from production and processing. For example, in the mechanical processing of titanium alloy products, operations such as cutting, milling, and drilling will generate a large amount of flaky scrap. These scraps usually have certain size and shape regularity and can be directly recycled. Scrap can be the dismantling of scrap titanium alloy products. From the dismantling of scrap titanium alloy equipment and components, flaky materials of different shapes and sizes can be obtained. Equipment such as titanium alloy reactors and heat exchangers used in the chemical industry can be dismantled after being scrapped to obtain flaky titanium alloy scrap suitable for recycling. Scrap can be the production waste of titanium alloy plates. In the rolling process of titanium alloy plates, flaky scrap will be generated due to edge trimming, unqualified size, etc. The material of these scraps is the same as that of finished plates, and they are high-quality recycled raw materials.

[0035] In some embodiments, a shot blasting machine is used to blast the waste material to remove the oxide scale and rust on the surface. Crushing: The waste material after shot blasting is crushed to ensure that its size is suitable for subsequent processing. Magnetic separation: The oxide scale and rust are separated by a magnetic separator to ensure the purity of the waste material.

[0036] In some embodiments, the step of cleaning the residual waste of titanium and titanium alloys includes: Cutting scrap plates of titanium and titanium alloys to meet the size requirements; According to the surface condition of the residual material, pickling and / or alkali washing are performed; when pickling, the pickling solution contains 10-15% hydrochloric acid by volume and 0.5-1% corrosion inhibitor by volume, the pickling temperature is 30-40℃, and the pickling time is 10-20min. During the pickling process, the acid reacts chemically with the oxide scale and rust, causing them to dissolve and fall off. After pickling, rinse with clean water immediately, and then neutralize it. The flake material can be soaked in 5-10% sodium carbonate solution for 5-10min, and finally rinsed with clean water until neutral.

[0037] When alkali washing is performed, the alkali washing solution contains 5-10g / L sodium hydroxide, 20-30g / L sodium carbonate, 10-15g / L sodium phosphate, the alkali washing temperature is 50-70°C, and the alkali washing time is 15-30min. During the alkali washing process, the alkali solution is used to react with the oil to undergo saponification and emulsification to remove the surface oil. After soaking, rinse the flakes with clean water until they are neutral.

[0038] Ultrasonic cleaning equipment with a frequency of 20-40kHz and a power of 500-1000W is used to ultrasonically clean the residual waste materials after acid washing and / or alkali washing. The cleaning liquid is deionized water or distilled water to further remove oil and impurities. The residual waste materials after ultrasonic cleaning are dried to ensure their dry state during the smelting process. Specifically, the sheet materials after acid washing and alkali washing are placed in an ultrasonic cleaning tank. The cleaning liquid in the tank can be deionized water or distilled water, and an appropriate amount of surfactant (such as sodium dodecylbenzene sulfonate 0.5-1g / L) is added to enhance the cleaning effect. Turn on the ultrasonic generator, and use the cavitation, acceleration and straight flow effects generated by ultrasonic waves in the cleaning liquid to further peel, emulsify and disperse the residual dirt on the surface and gaps of the sheet materials. The ultrasonic cleaning time is 10-20min. After cleaning, rinse the sheet materials with clean water to remove the residual cleaning liquid and dirt on the surface.

[0039] After the above cleaning steps, the flakes can be rinsed multiple times, and can be rinsed with running water to ensure that all residual chemical reagents and dirt are removed. The number of rinses should be no less than 3 times, and the rinsing time should be no less than 5 minutes each time.

[0040] Finally, the flakes 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. The drying time depends on the thickness and quantity of the flakes, ranging from 10-30min. 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 flakes should be stored in a dry and clean environment to avoid re-contamination.

[0041] In some embodiments, the step of performing vacuum electromagnetic suspension melting on the residual waste material and the alloy raw material includes: 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 filling pressure 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] When the scrap material includes industrial pure titanium, the alloy raw materials are molybdenum blocks and nickel blocks. The scrap material can also be all TA10 titanium alloy scrap material, in which case no alloy raw materials are required.

[0047] 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 raw material is melted once. The melting current is 300A at the beginning, and it is kept for 3 minutes; it is increased from 300A to 400A, and it is kept for 2 minutes; it is increased from 400A to 500A, and it is kept for 2 minutes; it is increased from 500A to 600A, and it is kept for 2 minutes; it is increased from 600A to 750A, and it is kept for 2 minutes; it is increased from 750A to 850A, and it is kept for 1 minute; it is increased from 850A to 950A, and it is kept for 30 seconds; it is increased from 950A to 1100A, and it is kept for 5 seconds; then it is kept warm for 5 minutes, and the melting power is 480-500kw. The raw material is 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 the 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 melted twice. The melting current setting value and cooling time are the same as those of the primary melting 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.

[0048] 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 3 As 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.

[0049] 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.

[0050] In some embodiments, the step of hot rolling the rolled slab comprises: The forged TA10 titanium alloy ingot is heated to 950-1000° C. in an electric heating furnace and then roughly rolled to prepare a titanium strip blank; The titanium strip blank is finely rolled to prepare TA10 titanium alloy strip with a thickness of 0.3-3 mm. After hot rolling, it is naturally cooled to ensure the surface quality of the product.

[0051] In some embodiments, the step of heating the forged TA10 ingot to 950-1000° C. in an electric heating furnace and then performing rough rolling comprises: 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] In some embodiments, the step of placing the residual waste material and the alloy raw material in a water-cooled crucible of a vacuum electromagnetic suspension furnace according to the target composition range of the TA10 titanium alloy ingot comprises: The target composition range is Ni: 0.6-0.9; Mo: 0.2-0.4; the alloy element ratio is determined according to the target composition range as Ni: 0.75; Mo: 0.3; the smelting raw materials are determined according to the alloy element ratio as scrap flakes, molybdenum blocks and nickel blocks. Metal raw materials of any shape can be smelted by vacuum electromagnetic levitation smelting, such as block, powder, flake, shavings, sponge and other shapes. Since the metal raw materials have no contact with the water-cooled crucible under the action of the Lorentz force during the smelting process, the impurities in the water-cooled crucible are avoided from contaminating the metal raw materials, and the purity of the TA10 titanium alloy ingot is improved. In addition, since the smelting temperature of the vacuum electromagnetic levitation smelting equipment exceeds 3000°C, the refractory metal Mo can be fully smelted.

[0059] In some embodiments, the step of placing the residual waste material and the alloy raw material in a water-cooled crucible of the vacuum electromagnetic suspension furnace according to the target composition range of the TA10 titanium alloy ingot also includes: The smelting raw materials are placed in a water-cooled crucible of a vacuum electromagnetic levitation furnace according to the melting points and shapes of different smelting raw materials, and vacuum electromagnetic levitation smelting is performed on the smelting raw materials in the water-cooled crucible. Specifically, a gap is set between the molybdenum block and the nickel block, and the titanium sheet is located in the gap so that liquid titanium can surround the molybdenum block and the nickel block, so that these block raw materials can be more easily mixed with liquid titanium after melting, and the composition of the entire melt is made more uniform through convection.

[0060] A specific embodiment of the method for preparing the TA10 strip of the present invention is described below: The target composition range of TA10 titanium alloy ingot is Ni: 0.6-0.9; Mo: 0.2-0.4, and the alloy element ratio is Ni: 0.75; Mo: 0.3. According to the alloy element ratio, the smelting raw materials are determined to be industrial pure titanium scraps, molybdenum blocks and nickel blocks. According to the melting point and shape of different smelting raw materials, the smelting raw materials are placed in the water-cooled crucible of the vacuum electromagnetic suspension furnace, and the smelting raw materials in the water-cooled crucible are subjected to vacuum electromagnetic suspension melting.

[0061] The raw materials are melted once, and the water-cooled crucible of the vacuum suspension melting furnace is 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] The above-mentioned TA10 strip preparation method makes the TA10 titanium alloy strip more uniform and fine in structure, the grain size can be controlled at 5-10μm, the mechanical properties are significantly improved, the tensile strength is increased by 10-15%, the yield strength is increased by 8-12%, the elongation after fracture is increased by 5-10%, the hardness value is more uniform and stable, the bending performance is good, and no cracks are generated. The dimensional accuracy of the strip 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, there are no obvious defects, and it meets the requirements of high-end application fields.

[0066] 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 preparing TA10 strip, characterized in that: The following steps are involved: Cleaning the scraps of titanium and titanium alloys, wherein the scraps are in the form of flakes; Placing the residual waste material and the alloy raw material in a water-cooled crucible of a vacuum electromagnetic suspension furnace according to the target composition range of the TA10 titanium alloy ingot, and performing vacuum electromagnetic suspension melting on the residual waste material and the alloy raw material to prepare the TA10 titanium alloy ingot; Forging the TA10 titanium alloy ingot to prepare a rolled slab; The rolled slab is hot rolled to prepare a TA10 titanium alloy strip.

2. The method for preparing the TA10 strip according to claim 1, characterized in that: The scrap material has a thickness of 3-5 mm, a length of 20-30 mm, and a width of 20-30 mm; the grade of the scrap material is industrial pure titanium or TA10.

3. The method for preparing the TA10 strip according to claim 2, characterized in that: The steps for cleaning the residual waste of titanium and titanium alloys include: Cutting the scrap plate of titanium and titanium alloy so that the scrap plate meets the size requirements; Acid washing and / or alkali washing are performed according to the surface condition of the residual waste material; when acid washing is performed, the acid washing solution contains 10-15% by volume of hydrochloric acid and 0.5-1% by volume of a corrosion inhibitor, the acid washing temperature is 30-40°C, and the acid washing time is 10-20min; when alkali washing is performed, the alkali washing solution contains 5-10g / L of sodium hydroxide, 20-30g / L of sodium carbonate, and 10-15g / L of sodium phosphate, the alkali washing temperature is 50-70°C, and the alkali washing time is 15-30min; Ultrasonic cleaning equipment with a frequency of 20-40kHz and a power of 500-1000W is used to ultrasonically clean the residual waste material after acid washing and / or alkali washing, and the cleaning liquid is deionized water or distilled water.

4. The method for preparing the TA10 strip according to claim 3, characterized in that: The step of performing vacuum electromagnetic suspension smelting on the residual waste material and the alloy raw material comprises: 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 filling pressure 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.

5. The method for preparing the TA10 strip according to claim 4, characterized in that: The step of performing vacuum electromagnetic suspension smelting on the residual waste material and the alloy raw material also includes: The scrap material and the alloy raw material are melted once, with a cooling time of 90 min-120 min, to prepare a primary ingot; the primary ingot is reversed and melted twice, with the melting parameters being the same as those of 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 those of the primary melting, to prepare a TA10 titanium alloy ingot.

6. The method for preparing TA10 strip according to claim 1, characterized in that: The step of hot rolling the rolled slab comprises: The forged TA10 titanium alloy ingot is heated to 950-1000° C. in an electric heating furnace and then roughly rolled to prepare a titanium strip blank; The titanium strip blank is subjected to precision rolling to prepare a TA10 titanium alloy strip with a thickness of 0.3-3 mm.

7. The method for preparing TA10 strip according to claim 6, characterized in that: The step of heating the forged TA10 ingot to 950-1000° C. in an electric heating furnace and then performing rough rolling comprises: The forged TA10 titanium alloy ingot is heated to 950-1000° C. for a holding time of 0.5-1.5 h; and rolled by a four-roll reversible rolling mill with a rolling speed set at 5.0-5.5 m / s to prepare the titanium strip blank with a thickness of 35-45 mm.

8. The method for preparing TA10 strip according to claim 7, characterized in that: 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 of the titanium strip 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.

9. The method for preparing TA10 strip according to claim 8, characterized in that: Before the step of fine rolling the titanium strip blank, the method further comprises: 8-12 pieces of steel strips are rolled through a six-roll or twenty-roll mill so that an oxide film is formed on the surface of the working rolls.

10. The method for preparing TA10 strip according to any one of claims 1 to 9, characterized in that: After the step of hot rolling the rolled slab, the method further comprises: Cold rolling the hot-rolled titanium strip blank at a rolling speed of 5-15 m / s and a tension of 50-150 MPa to prepare the 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.

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